Oppenheimer Main Street Funds NCSR Certified annual shareholder report (management investment company)

Oppenheimer Main Street Funds N-CSRCertified annual shareholder report (management investment company)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED

MANAGEMENT INVESTMENT COMPANIES

Investment Company Act file number 811-5360

Oppenheimer Main Street Funds

(Exact name of registrant as specified in charter)

6803 South Tucson Way, Centennial, Colorado 80112-3924

(Address of principal executive offices) (Zip code)

Arthur S. Gabinet

OFI Global Asset Management, Inc.

225 Liberty Street, New York, New York 10281-1008

(Name and address of agent for service)

Registrant’s telephone number, including area code: (303) 768-3200

Date of fiscal year end: August 31

Date of reporting period: 8/29/2014

Item 1. Reports to Stockholders.

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Table of Contents



Fund Performance Discussion			3

Top Holdings and Allocations			7

Fund Expenses			10

Statement of Investments			12

Statement of Assets and Liabilities			15

Statement of Operations			17

Statements of Changes in Net Assets			19

Financial Highlights			20

Notes to Financial Statements			26

Report of Independent Registered Public Accounting Firm			39

Federal Income Tax Information			40

Board Approval of the Fund’s Investment Advisory Agreement			41

Portfolio Proxy Voting Policies and Procedures; Updates to Statement of Investments			44

Trustees and Officers			45

Privacy Policy Notice			52

Class A Shares

AVERAGE ANNUAL TOTAL RETURNS AT 8/29/14*


	Class A Shares of the Fund
	Without Sales Charge	With Sales Charge	S&P 500 Index
1-Year	25.20%	18.00%	25.25%

5-Year	15.88	14.52	16.88

10-Year	7.74	7.10	8.38

Performance data quoted represents past performance, which does not guarantee future results. The investment return and principal value of an investment in the Fund will fluctuate so that an investor’s shares, when redeemed, may be worth more or less than their original cost. Fund returns include changes in share price, reinvested distributions, and a 5.75% maximum applicable sales charge except where “without sales charge” is indicated. Current performance may be lower or higher than the performance quoted. Returns do not consider capital gains or income taxes on an individual’s investment. For performance data current to the most recent month-end, visit oppenheimerfunds.com or call 1.800.CALL OPP (225.5677).

* August 29, 2014 was the last business day of the Fund’s fiscal year. See Note 1 of the accompanying Notes to Financial Statements. Index returns are calculated through August 31, 2014

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Fund Performance Discussion

The Fund’s Class A shares (without sales charge) produced a total return of 25.20% during the reporting period. On a relative basis, the Fund performed in line with its benchmark, the S&P 500 Index (the “Index”), which returned 25.25% during the reporting period. The Fund outperformed the Index within the health care, industrials and materials sectors, due primarily to stronger relative stock selection. An underweight position in telecommunication services also benefited the Fund’s relative performance. The Fund underperformed the Index within the consumer staples and energy sectors as a result of less favorable stock selection.

MARKET OVERVIEW

The reporting period began in the wake of market turmoil after the Federal Reserve (the “Fed”) signaled an earlier-than-expected shift away from its massive quantitative easing program. However, by the start of the reporting period, it had become clearer that a reduction in quantitative easing did not necessarily portend an imminent increase in short-term interest rates. When the Fed actually announced in December that it would

reduce its asset purchases by $10 billion a month, its decision to taper was met with relative calm in financial markets.

Markets once again turned volatile to start 2014 amid fears that political and economic instability in the world’s emerging markets might further dampen the U.S. economic recovery. While these fears generally failed to materialize, economic activity was

COMPARISON OF CHANGE IN VALUE OF $10,000 HYPOTHETICAL INVESTMENTS IN:

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constrained by unusually harsh winter weather over much of the United States, which caused downturns in consumer spending, corporate investment, and business inventory replenishment. Despite additional cuts in quantitative easing and signs of ongoing strength in U.S. labor markets, U.S. Gross Domestic Product (“GDP”) contracted at a surprising 2.1% annualized rate over the first quarter.

However, equities recovered in February and generally resumed their upward trend through the end of the reporting period, with dips in April and July. Economic data released in the second quarter also improved, as the unemployment rate fell to 6.3% in April, the economy finally regained all of the jobs lost during the 2008 recession, and the U.S. stock market achieved record highs. The U.S. Department of Commerce later estimated that U.S. GDP rebounded at a robust 4.6% annualized rate during the second quarter. Markets were also buoyed by additional stimulative monetary policies enacted by central banks throughout the world. Among those actions, the European Central Bank (the “ECB”) announced numerous measures in June, including a benchmark interest rate cut, the introduction of a negative deposit rate to encourage banks to lend, among various other measures to flood the system with liquidity. Beyond that, the ECB said it would prepare to purchase packages of loans from banks to allow for increased lending. The Fed implemented further reductions in its bond purchasing program, putting the

quantitative easing program on track for elimination in the fall.

There was also a pick-up in mergers and acquisitions (M&A) this reporting period. A driving force that has garnered considerable headline attention was Corporate America’s aim to put the cash that has built-up on overseas’ balance sheets to productive use. This, combined with an opportunity to lower overall corporate tax rates, resulted in a plethora of proposed acquisitions targeted at companies domiciled in desirable geographic tax havens.

FUND REVIEW

Top contributing holdings this reporting period included Apple, Inc., Allergan, Inc. and Canadian National Railway Co. Apple performed well during the second half of 2013 due to excitement surrounding the introduction of two new iPhones as well as the addition of China Mobile as a distribution partner. Apple also rallied strongly in April 2014 after iPhone sales came in higher than analysts anticipated and the company announced a 7-for-1 stock split and increased both its dividend and share repurchases. Allergan is a leading maker of eye care, skin care and aesthetic products, including Botox. Allergan’s stock price jumped when pharmaceutical firm Valeant, in conjunction with activist investor Bill Ackman of Pershing Square, announced their intention to acquire the company. While Allergan’s management has so far resisted this overture, on the premise that the acquisition price underestimates the company’s worth,

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Allergan’s stock price has remained elevated, trading within close range of the valuation proposed by the Valeant/Pershing Square team. After severe winter weather that disrupted freight travel throughout North America, rail carrier Canadian National Railway started catching up on delayed customer shipping volumes. Additionally, demand continued to grow from the non-conventional shale oil and gas fields as crude-by-rail gains share against other forms of transportation. Expected increases in volume shipments and improvements in the company’s operating ratio have resulted in rising earnings estimates, supporting the stock’s solid performance.

Detractors from performance this reporting period included Genworth Financial, Inc., International Business Machines Corp. (“IBM”) and Diageo plc. Genworth Financial is a provider of insurance, wealth management, investment and financial solutions. Shares of Genworth fell in the closing months of the period after the company announced it would conduct a comprehensive review of its long-term care insurance business, which saw a drop in operating profit in the second quarter of 2014. IBM reported disappointing revenues and earnings over the second half of 2013, due in part to delayed signings of new software and hardware bookings, and surprising weakness in revenue growth from emerging markets, particularly China. Cash generation — a key element of our investment thesis — also disappointed. We exited our position in IBM. Diageo is a

leading spirits company based in the United Kingdom that experienced declines amid weakness in emerging markets.

STRATEGY & OUTLOOK

Corporate profitability — at, or near, peak levels — looks vulnerable, especially if employment picks-up and wage inflation begins to affect profit margins. In our view, productivity gains and even the pick-up in M&A activity could help sustain operating profitability. However, after tax margins may be poised to contract as these have benefited greatly from financial engineering, including lower tax rates and, more importantly, lower cost of debt financing due to the Fed’s actions. We believe both are likely to have a diminished impact going forward.

While we are mindful of the potential pressure on profitability, we are also increasingly cognizant of “industry disruptors.” New and innovative technologies have always had a transformational effect, but other forms of disruption are now becoming pervasive across industries. The emergence of online retailing, the boom of shale oil and gas in North America, and the Affordable Care Act in health care are examples of industry disruptors likely to have a substantial and sustainable impact. These disruptors can be either opportunities or threats. Our job is to figure out which.

Given this backdrop, our approach remains consistent. We aim to construct an “all weather” portfolio by targeting companies

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that we believe have: 1) sustainable competitive advantages; 2) skilled management with a proven track record of executing effectively; and 3) financial resources to generate improving profitability, gain market share, and/or return significant cash to shareholders. During times of

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Manind Govil, CFA

Portfolio Manager

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Paul Larson¹

Portfolio Manager

1. Paul Larson became a Portfolio Manager in February 2014.

volatile or slow economic growth such companies frequently widen their lead over weaker competitors. We seek to invest in companies characterized by these qualities at compelling valuations and believe this disciplined approach is essential in seeking to generate superior long-term performance.

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Benjamin Ram

Portfolio Manager

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Top Holdings and Allocations*

TOP TEN COMMON STOCK HOLDINGS


Apple, Inc.		4.2%
Chevron Corp.		3.1
Noble Energy, Inc.		3.1
National Oilwell Varco, Inc.		2.9
General Electric Co.		2.9
Citigroup, Inc.		2.9
Google, Inc., Cl. C		2.9
Gilead Sciences, Inc.		2.8
Philip Morris International, Inc.		2.7
Mondelez International, Inc., Cl. A		2.7

Portfolio holdings and allocations are subject to change. Percentages are as of August 29, 2014, and are based on net assets. For more current Fund holdings, please visit oppenheimerfunds.com.

TOP TEN COMMON STOCK INDUSTRIES


Pharmaceuticals		8.8%
Internet Software & Services		8.0
Commercial Banks		6.9
Oil, Gas & Consumable Fuels		6.2
Technology Hardware, Storage & Peripherals		5.4
Insurance		5.0
Specialty Retail		4.9
IT Services		4.9
Diversified Financial Services		3.9
Media		3.4

Portfolio holdings and allocations are subject to change. Percentages are as of August 29, 2014, and are based on net assets.

SECTOR ALLOCATION

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Portfolio holdings and allocations are subject to change. Percentages are as of August 29, 2014, and are based on the total market value of common stocks.

*August 29, 2014 was the last business day of the Fund’s fiscal year. See Note 1 of the accompanying Notes to Financial Statements.

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Share Class Performance

AVERAGE ANNUAL TOTAL RETURNS WITHOUT SALES CHARGE AS OF 8/29/14


	Inception Date		1-Year		5-Year		10-Year
Class A (MSIGX)		2/3/88		25.20%		15.88%		7.74%
Class B (OMSBX)		10/3/94		24.22%		14.87%		7.24%
Class C (MIGCX)		12/1/93		24.28%		15.02%		6.94%
Class I (OMSIX)		12/29/11		25.73%		21.44% *		N/A
Class R (OMGNX)		3/1/01		24.88%		15.59%		7.44%
Class Y (MIGYX)		11/1/96		25.52%		16.33%		8.18%
AVERAGE ANNUAL TOTAL RETURNS WITH SALES CHARGE AS OF 8/29/14
	Inception Date		1-Year		5-Year		10-Year
Class A (MSIGX)		2/3/88		18.00%		14.52%		7.10%
Class B (OMSBX)		10/3/94		19.22%		14.64%		7.24%
Class C (MIGCX)		12/1/93		23.28%		15.02%		6.94%
Class I (OMSIX)		12/29/11		25.73%		21.44% *		N/A
Class R (OMGNX)		3/1/01		23.88%		15.59%		7.44%
Class Y (MIGYX)		11/1/96		25.52%		16.33%		8.18%

*Shows performance since inception

Performance data quoted represents past performance, which does not guarantee future results. The investment return and principal value of an investment in the Fund will fluctuate so that an investor’s shares, when redeemed, may be worth more or less than their original cost. Current performance may be lower or higher than the performance quoted. Returns do not consider capital gains or income taxes on an individual’s investment. For performance data current to the most recent month-end, visit oppenheimerfunds.com or call 1.800.CALL OPP (225.5677). Fund returns include changes in share price, reinvested distributions, and the applicable sales charge: for Class A shares, the current maximum initial sales charge of 5.75%; for Class B shares, the contingent deferred sales charge of 5% (1-year) and 2% (5-year); and for Class C shares, the contingent deferred sales charge (“CDSC”) of 1% for the 1-year period. Prior to 7/1/14, Class R shares were named Class N shares. Beginning 7/1/14, new purchases of Class R shares will no longer be subject to a CDSC upon redemption (any CDSC will remain in effect for purchases prior to 7/1/14). There is no sales charge for Class I and Class Y shares. Because Class B shares convert to Class A shares 72 months after purchase, the 10-year return for Class B shares uses Class A performance for the period after conversion.

The Fund’s performance is compared to the performance of the S&P 500 Index. The S&P 500 Index is an index of large-capitalization equity securities that is a measure of the general domestic stock market. The Index is unmanaged and cannot be purchased directly by investors. While index comparisons may be useful to provide a benchmark for the Fund’s performance, it must be noted that the Fund’s investments are not limited to the investments comprising the Index. Index performance includes reinvestment of income, but does not reflect transaction costs, fees, expenses or taxes. Index performance is shown for illustrative purposes only as a benchmark for the Fund’s performance, and does not predict or depict

8 OPPENHEIMER MAIN STREET FUND

performance of the Fund. The Fund’s performance reflects the effects of the Fund’s business and operating expenses.

The Fund’s investment strategy and focus can change over time. The mention of specific fund holdings does not constitute a recommendation by OppenheimerFunds, Inc. or its affiliates.

Before investing in any of the Oppenheimer funds, investors should carefully consider a fund’s investment objectives, risks, charges and expenses. Fund prospectuses and summary prospectuses contain this and other information about the funds, and may be obtained by asking your financial advisor, visiting oppenheimerfunds.com, or calling 1.800.CALL OPP (225.5677). Read prospectuses and summary prospectuses carefully before investing.

Shares of Oppenheimer funds are not deposits or obligations of any bank, are not guaranteed by any bank, are not insured by the FDIC or any other agency, and involve investment risks, including the possible loss of the principal amount invested.

9 OPPENHEIMER MAIN STREET FUND

Fund Expenses

Fund Expenses. As a shareholder of the Fund, you incur two types of costs: (1) transaction costs, which may include sales charges (loads) on purchase payments, contingent deferred sales charges on redemptions; and (2) ongoing costs, including management fees; distribution and service fees; and other Fund expenses. These examples are intended to help you understand your ongoing costs (in dollars) of investing in the Fund and to compare these costs with the ongoing costs of investing in other mutual funds.

The examples are based on an investment of $1,000.00 invested at the beginning of the period and held for the entire 6-month period ended August 29, 2014.

Actual Expenses. The first section of the table provides information about actual account values and actual expenses. You may use the information in this section for the class of shares you hold, together with the amount you invested, to estimate the expense that you paid over the period. Simply divide your account value by $1,000.00 (for example, an $8,600.00 account value divided by $1,000.00 = 8.60), then multiply the result by the number in the first section under the heading entitled “Expenses Paid During Period” to estimate the expenses you paid on your account during this period.

Hypothetical Example for Comparison Purposes. The second section of the table provides information about hypothetical account values and hypothetical expenses based on the Fund’s actual expense ratio for each class of shares, and an assumed rate of return of 5% per year for each class before expenses, which is not the actual return. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period. You may use this information to compare the ongoing costs of investing in the Fund and other funds. To do so, compare this 5% hypothetical example for the class of shares you hold with the 5% hypothetical examples that appear in the shareholder reports of the other funds.

Please note that the expenses shown in the table are meant to highlight your ongoing costs only and do not reflect any transactional costs, such as front-end or contingent deferred sales charges (loads). Therefore, the “hypothetical” section of the table is useful in comparing ongoing costs only, and will not help you determine the relative total costs of owning different funds. In addition, if these transactional costs were included, your costs would have been higher.

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Actual	Beginning Account Value March 1, 2014	Ending Account Value August 29, 2014	Expenses Paid During 6 Months Ended August 29, 2014
Class A	$ 1,000.00	$ 1,075.00	$ 4.82
Class B	1,000.00	1,070.90	8.76
Class C	1,000.00	1,070.90	8.71
Class I	1,000.00	1,077.20	2.59
Class R	1,000.00	1,073.60	6.12
Class Y	1,000.00	1,076.30	3.58

Hypothetical (5% return before expenses)
Class A	1,000.00	1,020.29	4.70
Class B	1,000.00	1,016.50	8.53
Class C	1,000.00	1,016.55	8.48
Class I	1,000.00	1,022.44	2.52
Class R	1,000.00	1,019.05	5.96
Class Y	1,000.00	1,021.49	3.48

Expenses are equal to the Fund’s annualized expense ratio for that class, multiplied by the average account value over the period, multiplied by 182/365 (to reflect the one-half year period). Those annualized expense ratios, excluding indirect expenses from affiliated funds, based on the 6-month period ended August 29, 2014 are as follows:


Class	Expense Ratios
Class A		0.93	%
Class B		1.69
Class C		1.68
Class I		0.50
Class R		1.18
Class Y		0.69

The expense ratios reflect voluntary and/or contractual waivers and/or reimbursements of expenses by the Fund’s Manager and Transfer Agent. Some of these undertakings may be modified or terminated at any time, as indicated in the Fund’s prospectus. The “Financial Highlights” tables in the Fund’s financial statements, included in this report, also show the gross expense ratios, without such waivers or reimbursements and reduction to custodian expenses, if applicable.

11 OPPENHEIMER MAIN STREET FUND

STATEMENT OF INVESTMENTS August 29, 2014*


	Shares		Value

Common Stocks—98.1%

Consumer Discretionary—11.6%

Auto Components—1.5%
Delphi Automotive plc		1,576,910	$	109,721,398


Automobiles—1.2%
General Motors Co.		2,596,550		90,359,940


Media—3.4%
Comcast Corp., Cl. A		3,498,000		191,445,540

Twenty-First Century Fox, Inc., Cl. A		1,680,880		59,536,770

				250,982,310


Specialty Retail—4.9%
AutoZone, Inc.¹		346,557		186,738,774

Home Depot, Inc. (The)		1,024,500		95,790,750

TJX Cos., Inc. (The)		1,364,920		81,362,881

				363,892,405


Textiles, Apparel & Luxury Goods—0.6%
PVH Corp.		356,330		41,597,964


Consumer Staples—9.1%

Beverages—2.1%
Diageo plc		5,198,600		153,295,645


Food Products—2.7%
Mondelez International, Inc., Cl. A		5,533,020		200,239,994


Household Products—1.6%
Henkel AG & Co. KGaA		1,243,624		118,261,905


Tobacco—2.7%
Philip Morris International, Inc.		2,351,908		201,276,287


Energy—9.1%

Energy Equipment & Services—2.9%
National Oilwell Varco, Inc.		2,504,830		216,492,457


Oil, Gas & Consumable Fuels—6.2%
Chevron Corp.		1,757,699		227,534,136

Noble Energy, Inc.		3,147,130		227,033,958

				454,568,094


	Shares		Value

Financials—17.7%

Commercial Banks—6.9%
CIT Group, Inc.		2,646,700	$	126,935,732

Citigroup, Inc.		4,135,180		213,582,047

JPMorgan Chase & Co.		2,850,820		169,481,249

				509,999,028


Consumer Finance—1.5%
Discover Financial Services		1,825,845		113,877,953


Diversified Financial Services—3.9%
CME Group, Inc.		1,959,600		150,007,380

McGraw Hill Financial, Inc.		1,667,928		135,318,998

				285,326,378


Insurance—5.0%
American International Group, Inc.		2,569,170		144,027,670

Genworth Financial, Inc., Cl. A¹		5,566,420		78,987,500

Lincoln National Corp.		981,380		54,015,155

Marsh & McLennan Cos., Inc.		1,686,450		89,550,495

				366,580,820


Real Estate Investment Trusts (REITs)—0.4%
Digital Realty Trust, Inc.		412,980		26,946,945


Health Care—15.9%

Biotechnology—2.8%
Gilead Sciences, Inc.¹		1,936,560		208,335,125


Health Care Equipment & Supplies—1.0%
Covidien plc		533,580		46,330,751

Intuitive Surgical, Inc.¹		62,800		29,516,628

				75,847,379


Health Care Providers & Services—3.3%
Express Scripts Holding Co.¹		1,892,322		139,899,365

UnitedHealth Group, Inc.		1,140,710		98,876,743

				238,776,108

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	Shares		Value

Pharmaceuticals—8.8%
AbbVie, Inc.		2,104,121	$	116,315,809

Actavis plc¹		751,100		170,484,678

Allergan, Inc.		670,110		109,683,605

Pfizer, Inc.		5,578,943		163,965,135

Zoetis, Inc.		2,424,682		85,930,730

				646,379,957


Industrials—10.4%

Commercial Services & Supplies—3.2%
Republic Services, Inc.		1,736,220		68,285,533

Tyco International Ltd.		3,750,038		167,326,695

				235,612,228


Industrial Conglomerates—2.9%
General Electric Co.		8,229,330		213,797,993


Machinery—2.4%
Deere & Co.		2,142,600		180,171,234


Road & Rail—1.9%
Canadian National Railway Co.		1,906,780		137,021,211


Information Technology—19.5%

Internet Software & Services—8.0%
eBay, Inc.¹		2,476,190		137,428,545

Facebook, Inc., Cl. A¹		1,321,340		98,862,659

Google, Inc., Cl. A¹		246,046		143,287,348

Google, Inc., Cl. C¹		371,256		212,209,930

				591,788,482


IT Services—4.9%
Amdocs Ltd.		1,936,830		91,224,693

MasterCard, Inc., Cl. A		2,072,840		157,142,000

Xerox Corp.		8,319,400		114,890,914

				363,257,607


Semiconductors & Semiconductor Equipment—1.2%
Applied Materials, Inc.		3,804,250		87,897,196


Technology Hardware, Storage & Peripherals—5.4%
Apple, Inc.		3,005,435		308,057,088


	Shares		Value

Technology Hardware, Storage & Peripherals (Continued)
Western Digital Corp.		846,200	$	87,167,062

				395,224,150


Materials—1.6%

Construction Materials—1.6%
Vulcan Materials Co.		1,916,253		121,452,115


Telecommunication Services—1.7%

Diversified Telecommunication Services—1.7%
Verizon Communications, Inc.		2,491,220		124,112,580


Utilities—1.5%

Electric Utilities—1.5%
Exelon Corp.		3,326,486		111,171,162

Total Common Stocks (Cost $5,062,926,977)				7,234,264,050


Preferred Stock—0.4%
Henkel AG & Co. KGaA, Preference (Cost $17,953,682)		237,455		24,897,421


Investment Company—1.1%

Oppenheimer Institutional Money Market Fund, Cl. E, 0.09%^2,3 (Cost $82,705,816)		82,705,816		82,705,816

Total Investments, at Value (Cost $5,163,586,475)		99.6%		7,341,867,287

Net Other Assets (Liabilities)		0.4		29,979,371

Net Assets		100.0%	$	7,371,846,658

13 OPPENHEIMER MAIN STREET FUND

STATEMENT OF INVESTMENTS Continued

Footnotes to Statement of Investments

*August 29, 2014 represents the last business day of the Fund’s reporting period. See Note 1 of the accompanying Notes.

1. Non-income producing security.

2. Is or was an affiliate, as defined in the Investment Company Act of 1940, at or during the period ended August 29, 2014, by virtue of the Fund owning at least 5% of the voting securities of the issuer or as a result of the Fund and the issuer having the same investment adviser. Transactions during the period in which the issuer was an affiliate are as follows:


	Shares August 30, 2013^a		Gross Additions		Gross Reductions		Shares August 29, 2014

Oppenheimer Institutional Money Market Fund, Cl. E		104,613,190		1,512,663,947		1,534,571,321		82,705,816

					Value		Income

Oppenheimer Institutional Money Market Fund, Cl. E					$	82,705,816	$	97,224

a. August 30, 2013 represents the last business day of the Fund’s 2013 fiscal year. See Note 1 of the accompanying Notes.

3. Rate shown is the 7-day yield as of August 29, 2014.

See accompanying Notes to Financial Statements.

14 OPPENHEIMER MAIN STREET FUND

STATEMENT OF ASSETS AND LIABILITIES August 29, 2014¹



Assets
Investments, at value—see accompanying statement of investments:
Unaffiliated companies (cost $5,080,880,659)	$	7,259,161,471
Affiliated companies (cost $82,705,816)		82,705,816

		7,341,867,287

Cash		100,001

Receivables and other assets:
Investments sold		92,685,060
Dividends		8,694,476
Shares of beneficial interest sold		1,530,670
Other		418,450

Total assets		7,445,295,944


Liabilities
Payables and other liabilities:
Investments purchased		65,545,267
Shares of beneficial interest redeemed		6,065,535
Distribution and service plan fees		1,374,197
Trustees’ compensation		369,825
Shareholder communications		31,514
Other		62,948

Total liabilities		73,449,286


Net Assets	$	7,371,846,658



Composition of Net Assets
Par value of shares of beneficial interest	$	140,583

Additional paid-in capital		4,548,163,370

Accumulated net investment income		25,915,965

Accumulated net realized gain on investments and foreign currency transactions		619,370,912

Net unrealized appreciation on investments and translation of assets and liabilities denominated in foreign currencies		2,178,255,828

Net Assets	$	7,371,846,658

1. August 29, 2014 represents the last business day of the Fund’s 2014 fiscal year. See Note 1 of the accompanying Notes.

15 OPPENHEIMER MAIN STREET FUND

STATEMENT OF ASSETS AND LIABILITIES Continued



Net Asset Value Per Share
Class A Shares:
Net asset value and redemption price per share (based on net assets of $5,429,873,822 and 102,970,167 shares of beneficial interest outstanding)	$	52.73
Maximum offering price per share (net asset value plus sales charge of 5.75% of offering price)	$	55.95

Class B Shares:
Net asset value, redemption price (excludes applicable contingent deferred sales charge) and offering price per share (based on net assets of $185,704,604 and 3,657,283 shares of beneficial interest outstanding)	$	50.78

Class C Shares:
Net asset value, redemption price (excludes applicable contingent deferred sales charge) and offering price per share (based on net assets of $677,274,270 and 13,375,924 shares of beneficial interest outstanding)	$	50.63

Class I Shares:
Net asset value, redemption price and offering price per share (based on net assets of $295,518,594 and 5,631,864 shares of beneficial interest outstanding)	$	52.47

Class R Shares:
Net asset value, redemption price (excludes applicable contingent deferred sales charge) and offering price per share (based on net assets of $118,479,211 and 2,276,227 shares of beneficial interest outstanding)	$	52.05

Class Y Shares:
Net asset value, redemption price and offering price per share (based on net assets of $664,996,157 and 12,671,367 shares of beneficial interest outstanding)	$	52.48

See accompanying Notes to Financial Statements.

16 OPPENHEIMER MAIN STREET FUND

STATEMENTOF OPERATIONS For the Year Ended August 29, 2014¹



Investment Income
Dividends:
Unaffiliated companies (net of foreign withholding taxes of $561,212)	$	104,509,087
Affiliated companies		97,224

Interest		4,899

Other income		162,000

Total investment income		104,773,210


Expenses
Management fees		31,788,940

Distribution and service plan fees:
Class A		12,190,794
Class B		1,970,673
Class C		6,353,931
Class R²		560,977

Transfer and shareholder servicing agent fees:
Class A		10,340,911
Class B		546,215
Class C		1,298,988
Class I		61,033
Class R²		238,389
Class Y		1,255,145

Shareholder communications:
Class A		419,361
Class B		23,320
Class C		50,929
Class I		379
Class R²		4,614
Class Y		47,113

Trustees’ compensation		220,999

Custodian fees and expenses		50,208

Other		324,023

Total expenses		67,746,942
Less waivers and reimbursements of expenses		(144,507)

Net expenses		67,602,435

Net Investment Income		37,170,775

1. August 29, 2014 represents the last business day of the Fund’s 2014 fiscal year. See Note 1 of the accompanying Notes.

2. Effective July 1, 2014, Class N shares were renamed Class R. See Note 1 of the accompanying Notes.

17 OPPENHEIMER MAIN STREET FUND

STATEMENT OF OPERATIONS Continued



Realized and Unrealized Gain (Loss)
Net realized gain on:
Investments from unaffiliated companies	$	1,047,635,830
Foreign currency transactions		51,536

Net realized gain		1,047,687,366

Net change in unrealized appreciation/depreciation on:
Investments		446,649,647
Translation of assets and liabilities denominated in foreign currencies		(5,758,820)

Net change in unrealized appreciation/depreciation		440,890,827


Net Increase in Net Assets Resulting from Operations	$	1,525,748,968

See accompanying Notes to Financial Statements.

18 OPPENHEIMER MAIN STREET FUND

STATEMENTSOF CHANGES IN NET ASSETS


	Year Ended August 29, 2014¹		Year Ended August 30, 2013¹

Operations
Net investment income	$	37,170,775	$	50,308,766

Net realized gain		1,047,687,366		452,719,256

Net change in unrealized appreciation/depreciation		440,890,827		396,984,201

Net increase in net assets resulting from operations		1,525,748,968		900,012,223


Dividends and/or Distributions to Shareholders
Dividends from net investment income:
Class A		(32,462,343)		(45,859,228)
Class B		—		—
Class C		—		(1,160,384)
Class I		(1,274,578)		(118,640)
Class R²		(471,221)		(657,051)
Class Y		(8,563,438)		(5,745,955)

		(42,771,580)		(53,541,258)


Beneficial Interest Transactions
Net increase (decrease) in net assets resulting from beneficial interest transactions:
Class A		(254,468,541)		(377,598,983)
Class B		(63,195,646)		(72,598,234)
Class C		(42,487,169)		(50,416,841)
Class I		236,370,198		22,664,904
Class R²		(11,674,330)		(11,382,513)
Class Y		(206,670,797)		415,824,203

		(342,126,285)		(73,507,464)


Net Assets
Total increase		1,140,851,103		772,963,501

Beginning of period		6,230,995,555		5,458,032,054


End of period (including accumulated net investment income of $25,915,965 and $31,465,233, respectively)	$	7,371,846,658	$	6,230,995,555

1. August 29, 2014 and August 30, 2013 represent the last business days of the Fund’s respective reporting periods. See Note 1 of the accompanying Notes.

2. Effective July 1, 2014, Class N shares were renamed Class R. See Note 1 of the accompanying Notes.

See accompanying Notes to Financial Statements.

19 OPPENHEIMER MAIN STREET FUND

FINANCIAL HIGHLIGHTS


Class A	Year Ended August 29, 2014¹		Year Ended August 30, 2013¹		Year Ended August 31, 2012		Year Ended August 31, 2011		Year Ended August 31, 2010

Per Share Operating Data
Net asset value, beginning of period	$	42.39	$	36.69	$	30.93	$	27.17	$	26.17

Income (loss) from investment operations:
Net investment income²		0.29		0.37		0.25		0.20		0.21
Net realized and unrealized gain		10.36		5.73		5.67		3.73		1.04

Total from investment operations		10.65		6.10		5.92		3.93		1.25

Dividends and/or distributions to shareholders:
Dividends from net investment income		(0.31)		(0.40)		(0.16)		(0.17)		(0.25)

Net asset value, end of period	$	52.73	$	42.39	$	36.69	$	30.93	$	27.17



Total Return, at Net Asset Value³		25.20%		16.78%		19.21%		14.46%		4.75%

Ratios/Supplemental Data
Net assets, end of period (in thousands)	$	5,429,874	$	4,588,619	$	4,318,726	$	4,005,609	$	3,959,992

Average net assets (in thousands)	$	5,096,996	$	4,494,340	$	4,164,196	$	4,453,926	$	4,309,071

Ratios to average net assets:⁴
Net investment income		0.60%		0.95%		0.74%		0.62%		0.76%
Total expenses⁵		0.92%		0.93%		0.97%		0.99%		1.03%
Expenses after payments, waivers and/or reimbursements and reduction to custodian expenses		0.92%		0.93%		0.97%		0.99%		1.03%

Portfolio turnover rate		52%		46%		37%		35%		53%

1. August 29, 2014 and August 30, 2013 represent the last business days of the Fund’s respective reporting periods. See Note 1 of the accompanying Notes.

2. Per share amounts calculated based on the average shares outstanding during the period.

3. Assumes an initial investment on the business day before the first day of the fiscal period, with all dividends and distributions reinvested in additional shares on the reinvestment date, and redemption at the net asset value calculated on the last business day of the fiscal period. Sales charges are not reflected in the total returns. Total returns are not annualized for periods less than one full year. Returns do not reflect the deduction of taxes that a shareholder would pay on fund distributions or the redemption of fund shares.

4. Annualized for periods less than one full year.

5. Total expenses including indirect expenses from affiliated fund were as follows:

See accompanying Notes to Financial Statements.

20 OPPENHEIMER MAIN STREET FUND


Class B	Year Ended August 29, 2014¹		Year Ended August 30, 2013¹		Year Ended August 31, 2012		Year Ended August 31, 2011		Year Ended August 31, 2010

Per Share Operating Data
Net asset value, beginning of period	$	40.88	$	35.33	$	29.90	$	26.37	$	25.42

Income (loss) from investment operations:
Net investment income (loss)²		(0.10)		0.01		(0.05)		(0.09)		(0.02)
Net realized and unrealized gain		10.00		5.54		5.48		3.62		1.01

Total from investment operations		9.90		5.55		5.43		3.53		0.99

Dividends and/or distributions to shareholders:
Dividends from net investment income		0.00		0.00		0.00		0.00		(0.04)

Net asset value, end of period	$	50.78	$	40.88	$	35.33	$	29.90	$	26.37



Total Return, at Net Asset Value³		24.22%		15.71%		18.16%		13.39%		3.88%

Ratios/Supplemental Data
Net assets, end of period (in thousands)	$	185,705	$	205,386	$	245,172	$	267,723	$	355,717

Average net assets (in thousands)	$	199,044	$	224,582	$	257,205	$	332,239	$	390,057

Ratios to average net assets:⁴
Net investment income (loss)		(0.22)%		0.02%		(0.15)%		(0.28)%		(0.08)%
Total expenses⁵		1.74%		1.92%		1.97%		2.00%		2.05%
Expenses after payments, waivers and/or reimbursements and reduction to custodian expenses		1.73%		1.86%		1.85%		1.89%		1.88%

Portfolio turnover rate		52%		46%		37%		35%		53%

1. August 29, 2014 and August 30, 2013 represent the last business days of the Fund’s respective reporting periods. See Note 1 of the accompanying Notes.

2. Per share amounts calculated based on the average shares outstanding during the period.

4. Annualized for periods less than one full year.

5. Total expenses including indirect expenses from affiliated fund were as follows:

See accompanying Notes to Financial Statements.

21 OPPENHEIMER MAIN STREET FUND

FINANCIAL HIGHLIGHTS Continued


Class C	Year Ended August 29, 2014¹		Year Ended August 30, 2013¹		Year Ended August 31, 2012		Year Ended August 31, 2011		Year Ended August 31, 2010

Per Share Operating Data
Net asset value, beginning of period	$	40.74	$	35.22	$	29.77	$	26.20	$	25.27

Income (loss) from investment operations:
Net investment income (loss)²		(0.07)		0.07		0.00³		(0.04)		0.01
Net realized and unrealized gain		9.96		5.53		5.45		3.61		0.99

Total from investment operations		9.89		5.60		5.45		3.57		1.00

Dividends and/or distributions to shareholders:
Dividends from net investment income		0.00		(0.08)		0.00		0.00		(0.07)

Net asset value, end of period	$	50.63	$	40.74	$	35.22	$	29.77	$	26.20



Total Return, at Net Asset Value⁴		24.28%		15.92%		18.31%		13.63%		3.96%

Ratios/Supplemental Data
Net assets, end of period (in thousands)	$	677,274	$	582,360	$	550,341	$	520,988	$	522,449

Average net assets (in thousands)	$	641,903	$	568,419	$	535,180	$	577,960	$	565,220

Ratios to average net assets:⁵
Net investment income (loss)		(0.15)%		0.20%		0.00%⁶		(0.12)%		0.03%
Total expenses⁷		1.67%		1.68%		1.71%		1.73%		1.76%
Expenses after payments, waivers and/or reimbursements and reduction to custodian expenses		1.67%		1.68%		1.71%		1.73%		1.76%

Portfolio turnover rate		52%		46%		37%		35%		53%

1. August 29, 2014 and August 30, 2013 represent the last business days of the Fund’s respective reporting periods. See Note 1 of the accompanying Notes.

2. Per share amounts calculated based on the average shares outstanding during the period.

3. Less than $0.005 per share.

4. Assumes an initial investment on the business day before the first day of the fiscal period, with all dividends and distributions reinvested in additional shares on the reinvestment date, and redemption at the net asset value calculated on the last business day of the fiscal period. Sales charges are not reflected in the total returns. Total returns are not annualized for periods less than one full year. Returns do not reflect the deduction of taxes that a shareholder would pay on fund distributions or the redemption of fund shares.

5. Annualized for periods less than one full year.

6. Less than 0.005%.

7. Total expenses including indirect expenses from affiliated fund were as follows:

See accompanying Notes to Financial Statements.

22 OPPENHEIMER MAIN STREET FUND


Class I	Year Ended August 29, 2014¹		Year Ended August 30, 2013¹		Period Ended August 31, 2012²

Per Share Operating Data
Net asset value, beginning of period	$	42.33	$	36.82	$	32.31

Income (loss) from investment operations:
Net investment income³		0.51		0.50		0.29
Net realized and unrealized gain		10.30		5.75		4.22

Total from investment operations		10.81		6.25		4.51

Dividends and/or distributions to shareholders:
Dividends from net investment income		(0.67)		(0.74)		0.00

Net asset value, end of period	$	52.47	$	42.33	$	36.82



Total Return, at Net Asset Value⁴		25.73%		17.28%		13.96%

Ratios/Supplemental Data
Net assets, end of period (in thousands)	$	295,519	$	25,203	$	11

Average net assets (in thousands)	$	203,534	$	15,305	$	11

Ratios to average net assets:⁵
Net investment income		1.05%		1.26%		1.22%
Total expenses⁶		0.50%		0.51%		0.50%
Expenses after payments, waivers and/or reimbursements and reduction to custodian expenses		0.50%		0.51%		0.50%

Portfolio turnover rate		52%		46%		37%

1. August 29, 2014 and August 30, 2013 represent the last business days of the Fund’s respective reporting periods. See Note 1 of the accompanying Notes.

2. For the period from December 29, 2011 (inception of offering) to August 31, 2012.

3. Per share amounts calculated based on the average shares outstanding during the period.

5. Annualized for periods less than one full year.

6. Total expenses including indirect expenses from affiliated fund were as follows:

See accompanying Notes to Financial Statements.

23 OPPENHEIMER MAIN STREET FUND

FINANCIAL HIGHLIGHTS Continued


Class R	Year Ended August 29, 2014¹		Year Ended August 30, 2013¹		Year Ended August 31, 2012		Year Ended August 31, 2011		Year Ended August 31, 2010

Per Share Operating Data
Net asset value, beginning of period	$	41.85	$	36.17	$	30.49	$	26.77	$	25.80

Income (loss) from investment operations:
Net investment income²		0.16		0.26		0.16		0.12		0.14
Net realized and unrealized gain		10.23		5.66		5.59		3.68		1.02

Total from investment operations		10.39		5.92		5.75		3.80		1.16

Dividends and/or distributions to shareholders:
Dividends from net investment income		(0.19)		(0.24)		(0.07)		(0.08)		(0.19)

Net asset value, end of period	$	52.05	$	41.85	$	36.17	$	30.49	$	26.77



Total Return, at Net Asset Value³		24.88%		16.47%		18.91%		14.18%		4.48%

Ratios/Supplemental Data
Net assets, end of period (in thousands)	$	118,479	$	105,630	$	101,596	$	98,147	$	106,628

Average net assets (in thousands)	$	114,029	$	104,731	$	99,620	$	111,540	$	119,175

Ratios to average net assets:⁴
Net investment income		0.34%		0.68%		0.48%		0.37%		0.50%
Total expenses⁵		1.17%		1.20%		1.22%		1.23%		1.28%
Expenses after payments, waivers and/or reimbursements and reduction to custodian expenses		1.17%		1.20%		1.22%		1.23%		1.28%

Portfolio turnover rate		52%		46%		37%		35%		53%

1. August 29, 2014 and August 30, 2013 represent the last business days of the Fund’s respective reporting periods. See Note 1 of the accompanying Notes.

2. Per share amounts calculated based on the average shares outstanding during the period.

4. Annualized for periods less than one full year.

5. Total expenses including indirect expenses from affiliated fund were as follows:

See accompanying Notes to Financial Statements.

24 OPPENHEIMER MAIN STREET FUND


Class Y	Year Ended August 29, 2014¹		Year Ended August 30, 2013¹		Year Ended August 31, 2012		Year Ended August 31, 2011		Year Ended August 31, 2010

Per Share Operating Data
Net asset value, beginning of period	$	42.30	$	36.81	$	31.04	$	27.27	$	26.27

Income (loss) from investment operations:
Net investment income²		0.40		0.49		0.40		0.33		0.37
Net realized and unrealized gain		10.32		5.72		5.67		3.75		1.03

Total from investment operations		10.72		6.21		6.07		4.08		1.40

Dividends and/or distributions to shareholders:
Dividends from net investment income		(0.54)		(0.72)		(0.30)		(0.31)		(0.40)

Net asset value, end of period	$	52.48	$	42.30	$	36.81	$	31.04	$	27.27



Total Return, at Net Asset Value³		25.52%		17.18%		19.70%		14.94%		5.27%

Ratios/Supplemental Data
Net assets, end of period (in thousands)	$	664,996	$	723,798	$	242,186	$	117,659	$	98,434

Average net assets (in thousands)	$	655,922	$	469,824	$	192,143	$	117,050	$	436,261

Ratios to average net assets:⁴
Net investment income		0.84%		1.21%		1.16%		1.03%		1.30%
Total expenses⁵		0.67%		0.61%		0.54%		0.57%		0.49%
Expenses after payments, waivers and/or reimbursements and reduction to custodian expenses		0.67%		0.61%		0.54%		0.57%		0.49%

Portfolio turnover rate		52%		46%		37%		35%		53%

1. August 29, 2014 and August 30, 2013 represent the last business days of the Fund’s respective reporting periods. See Note 1 of the accompanying Notes.

2. Per share amounts calculated based on the average shares outstanding during the period.

4. Annualized for periods less than one full year.

5. Total expenses including indirect expenses from affiliated fund were as follows:

See accompanying Notes to Financial Statements.

25 OPPENHEIMER MAIN STREET FUND

NOTESTO FINANCIAL STATEMENTS August 29, 2014

1. Significant Accounting Policies

Oppenheimer Main Street Fund (the “Fund”) is a separate series of Oppenheimer Main Street Funds, a diversified open-end management investment company registered under the Investment Company Act of 1940, as amended. The Fund’s investment objective is to seek capital appreciation. The Fund’s investment adviser is OFI Global Asset Management, Inc. (“OFI Global” or the “Manager”), a wholly-owned subsidiary of OppenheimerFunds, Inc. (“OFI” or the “Sub-Adviser”). The Manager has entered into a sub-advisory agreement with OFI.

The Fund offers Class A, Class C, Class I, Class R and Class Y shares, and previously offered Class B shares for new purchase through June 29, 2012. Subsequent to that date, no new purchases of Class B shares are permitted, however reinvestment of dividend and/or capital gain distributions and exchanges of Class B shares into and from other Oppenheimer funds will be allowed. As of July 1, 2014, Class N shares were renamed Class R shares. Class N shares subject to a contingent deferred sales charge (“CDSC”) on July 1, 2014, will continue to be subject to a CDSC after the shares are renamed. Purchases of Class R shares occurring on or after July 1, 2014, will not be subject to a CDSC upon redemption. Class A shares are sold at their offering price, which is normally net asset value plus a front-end sales charge. Class C and Class R shares are sold, and Class B shares were sold, without a front-end sales charge but may be subject to a CDSC. Class R shares are sold only through retirement plans. Retirement plans that offer Class R shares may impose charges on those accounts. Class I and Class Y shares are sold to certain institutional investors or intermediaries without either a front-end sales charge or a CDSC, however, the intermediaries may impose charges on their accountholders who beneficially own Class I and Class Y shares. All classes of shares have identical rights and voting privileges with respect to the Fund in general and exclusive voting rights on matters that affect that class alone. Earnings, net assets and net asset value per share may differ due to each class having its own expenses, such as transfer and shareholder servicing agent fees and shareholder communications, directly attributable to that class. Class A, B, C and R shares have separate distribution and/or service plans under which they pay fees. Class I and Class Y shares do not pay such fees. Class B shares will automatically convert to Class A shares 72 months after the date of purchase.

The following is a summary of significant accounting policies consistently followed by the Fund.

Annual Periods. The last day of the Fund’s fiscal years was the last day the New York Stock Exchange was open for trading. The Fund’s financial statements have been presented through that date to maintain consistency with the Fund’s net asset value calculations used for shareholder transactions.

Investment in Oppenheimer Institutional Money Market Fund. The Fund is permitted to invest daily available cash balances in an affiliated money market fund. The Fund may invest the available cash in Class E shares of Oppenheimer Institutional Money Market Fund (“IMMF”) to seek current income while preserving liquidity. IMMF is a registered open-end management investment company, regulated as a money market fund under the Investment Company Act of 1940, as amended. The Manager is the investment adviser of IMMF, and the

26 OPPENHEIMER MAIN STREET FUND

1. Significant Accounting Policies (Continued)

Sub-Adviser provides investment and related advisory services to IMMF. When applicable, the Fund’s investment in IMMF is included in the Statement of Investments. Shares of IMMF are valued at their net asset value per share. As a shareholder, the Fund is subject to its proportional share of IMMF’s Class E expenses, including its management fee. The Manager will waive fees and/or reimburse Fund expenses in an amount equal to the indirect management fees incurred through the Fund’s investment in IMMF.

Foreign Currency Translation. The Fund’s accounting records are maintained in U.S. dollars. The values of securities denominated in foreign currencies and amounts related to the purchase and sale of foreign securities and foreign investment income are translated into U.S. dollars as of the close of the New York Stock Exchange (the “Exchange”), normally 4:00 P.M. Eastern time, on each day the Exchange is open for trading. Foreign exchange rates may be valued primarily using a reliable bank, dealer or service authorized by the Board of Trustees.

Reported net realized gains and losses from foreign currency transactions arise from sales of portfolio securities, sales and maturities of short-term securities, sales of foreign currencies, exchange rate fluctuations between the trade and settlement dates on securities transactions, and the difference between the amounts of dividends, interest, and foreign withholding taxes recorded on the Fund’s books and the U.S. dollar equivalent of the amounts actually received or paid. Net unrealized appreciation and depreciation on the translation of assets and liabilities denominated in foreign currencies arise from changes in the values of assets and liabilities, including investments in securities at fiscal period end, resulting from changes in exchange rates.

The effect of changes in foreign currency exchange rates on investments is separately identified from the fluctuations arising from changes in market values of securities held and reported with all other foreign currency gains and losses in the Fund’s Statement of Operations.

Allocation of Income, Expenses, Gains and Losses. Income, expenses (other than those attributable to a specific class), gains and losses are allocated on a daily basis to each class of shares based upon the relative proportion of net assets represented by such class. Operating expenses directly attributable to a specific class are charged against the operations of that class.

Federal Taxes. The Fund intends to comply with provisions of the Internal Revenue Code applicable to regulated investment companies and to distribute substantially all of its investment company taxable income, including any net realized gain on investments not offset by capital loss carryforwards, if any, to shareholders. Therefore, no federal income or excise tax provision is required. The Fund files income tax returns in U.S. federal and applicable state jurisdictions. The statute of limitations on the Fund’s tax return filings generally remain open for the three preceding fiscal reporting period ends.

The tax components of capital shown in the following table represent distribution requirements the Fund must satisfy under the income tax regulations, losses the Fund may be

27 OPPENHEIMER MAIN STREET FUND

NOTES TO FINANCIAL STATEMENTS Continued

1. Significant Accounting Policies (Continued)

able to offset against income and gains realized in future years and unrealized appreciation or depreciation of securities and other investments for federal income tax purposes.


Undistributed Net Investment Income	Undistributed Long-Term Gain		Accumulated Loss Carryforward^1,2,3		Net Unrealized Appreciation Based on cost of Securities and Other Investments for Federal Income Tax Purposes

$26,485,105		$622,816,592		$1,248,650		$2,176,058,796

1. As of August 29, 2014, the Fund had $1,248,650 of net capital loss carryforwards available to offset future realized capital gains, if any, and thereby reduce future taxable gain distributions. Details of the capital loss carryforwards are included in the table below. Capital loss carryovers with no expiration, if any, must be utilized prior to those with expiration dates.


Expiring

2016	$	811,554
2017		437,096

Total	$	1,248,650

Of these losses, $1,248,650 are subject to loss limitation rules resulting from merger activity. These limitations generally reduce the utilization of these losses to a maximum of $2,594,283 per year.

2. During the fiscal year ended August 29, 2014, the Fund utilized $369,031,408 of capital loss carryforward to offset capital gains realized in that fiscal year.

3. During the fiscal year ended August 30, 2013, the Fund utilized $452,146,453 of capital loss carryforward to offset capital gains realized in that fiscal year.

Net investment income (loss) and net realized gain (loss) may differ for financial statement and tax purposes. The character of dividends and distributions made during the fiscal year from net investment income or net realized gains may differ from their ultimate characterization for federal income tax purposes. Also, due to timing of dividends and distributions, the fiscal year in which amounts are distributed may differ from the fiscal year in which the income or net realized gain was recorded by the Fund.

Accordingly, the following amounts have been reclassified for August 29, 2014. Net assets of the Fund were unaffected by the reclassifications.


Increase to Paid-in Capital⁴	Increase to Accumulated Net Investment Income		Reduction to Accumulated Net Realized Gain on Investments⁴

$53,814,942		$51,537		$53,866,479

4. $53,814,942, all of which was long-term capital gain, was distributed in connection with Fund share redemptions.

The tax character of distributions paid during the years ended August 31, 2014 and August 31, 2013 was as follows:

28 OPPENHEIMER MAIN STREET FUND

1. Significant Accounting Policies (Continued)


	Year Ended August 31, 2014		Year Ended August 31, 2013

Distributions paid from:
Ordinary income	$	42,771,580	$	53,541,258

The aggregate cost of securities and other investments and the composition of unrealized appreciation and depreciation of securities and other investments for federal income tax purposes as of August 29, 2014 are noted in the following table. The primary difference between book and tax appreciation or depreciation of securities and other investments, if applicable, is attributable to the tax deferral of losses or tax realization of financial statement unrealized gain or loss.


Federal tax cost of securities	$	5,165,783,507

Gross unrealized appreciation	$	2,223,324,795
Gross unrealized depreciation		(47,265,999)

Net unrealized appreciation	$	2,176,058,796

Trustees’ Compensation. The Board of Trustees has adopted a compensation deferral plan for independent trustees that enables trustees to elect to defer receipt of all or a portion of the annual compensation they are entitled to receive from the Fund. For purposes of determining the amount owed to the Trustee under the plan, deferred amounts are treated as though equal dollar amounts had been invested in shares of the Fund or in other Oppenheimer funds selected by the Trustee. The Fund purchases shares of the funds selected for deferral by the Trustee in amounts equal to his or her deemed investment, resulting in a Fund asset equal to the deferred compensation liability. Such assets are included as a component of “Other” within the asset section of the Statement of Assets and Liabilities. Deferral of trustees’ fees under the plan will not affect the net assets of the Fund, and will not materially affect the Fund’s assets, liabilities or net investment income per share. Amounts will be deferred until distributed in accordance with the compensation deferral plan.

Dividends and Distributions to Shareholders. Dividends and distributions to shareholders, which are determined in accordance with income tax regulations and may differ from U.S. generally accepted accounting principles, are recorded on the ex-dividend date. Income and capital gain distributions, if any, are declared and paid annually or at other times as deemed necessary by the Manager.

Investment Income. Dividend income is recorded on the ex-dividend date or upon ex-dividend notification in the case of certain foreign dividends where the ex-dividend date may have passed. Non-cash dividends included in dividend income, if any, are recorded at the fair market value of the securities received. Interest income is recognized on an accrual basis. Discount and premium, which are included in interest income on the Statement of Operations, are amortized or accreted daily.

29 OPPENHEIMER MAIN STREET FUND

NOTES TO FINANCIAL STATEMENTS Continued

1. Significant Accounting Policies (Continued)

Custodian Fees. “Custodian fees and expenses” in the Statement of Operations may include interest expense incurred by the Fund on any cash overdrafts of its custodian account during the period. Such cash overdrafts may result from the effects of failed trades in portfolio securities and from cash outflows resulting from unanticipated shareholder redemption activity. The Fund pays interest to its custodian on such cash overdrafts, to the extent they are not offset by positive cash balances maintained by the Fund, at a rate equal to the Federal Funds Rate plus 0.50%. The “Reduction to custodian expenses” line item, if applicable, represents earnings on cash balances maintained by the Fund during the period. Such interest expense and other custodian fees may be paid with these earnings.

Security Transactions. Security transactions are recorded on the trade date. Realized gains and losses on securities sold are determined on the basis of identified cost.

Indemnifications. The Fund’s organizational documents provide current and former trustees and officers with a limited indemnification against liabilities arising in connection with the performance of their duties to the Fund. In the normal course of business, the Fund may also enter into contracts that provide general indemnifications. The Fund’s maximum exposure under these arrangements is unknown as this would be dependent on future claims that may be made against the Fund. The risk of material loss from such claims is considered remote.

Other. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates.

2. Securities Valuation

The Fund calculates the net asset value of its shares as of the close of the New York Stock Exchange (the “Exchange”), normally 4:00 P.M. Eastern time, on each day the Exchange is open for trading.

The Fund’s Board has adopted procedures for the valuation of the Fund’s securities and has delegated the day-to-day responsibility for valuation determinations under those procedures to the Manager. The Manager has established a Valuation Committee which is responsible for determining a “fair valuation” for any security for which market quotations are not “readily available.” The Valuation Committee’s fair valuation determinations are subject to review, approval and ratification by the Fund’s Board at its next regularly scheduled meeting covering the calendar quarter in which the fair valuation was determined.

Valuation Methods and Inputs

Securities are valued using unadjusted quoted market prices, when available, as supplied primarily by third party pricing services or dealers.

30 OPPENHEIMER MAIN STREET FUND

2. Securities Valuation (Continued)

The following methodologies are used to determine the market value or the fair value of the types of securities described below:

Securities traded on a registered U.S. securities exchange (including exchange-traded derivatives other than futures and futures options) are valued based on the last sale price of the security reported on the principal exchange on which it is traded, prior to the time when the Fund’s assets are valued. In the absence of a sale, the security is valued at the last sale price on the prior trading day, if it is within the spread of the current day’s closing “bid” and “asked” prices, and if not, at the current day’s closing bid price. A security of a foreign issuer traded on a foreign exchange, but not listed on a registered U.S. securities exchange, is valued based on the last sale price on the principal exchange on which the security is traded, as identified by the third party pricing service used by the Manager, prior to the time when the Fund’s assets are valued. If the last sale price is unavailable, the security is valued at the most recent official closing price on the principal exchange on which it is traded. If the last sales price or official closing price for a foreign security is not available, the security is valued at the mean between the bid and asked price per the exchange or, if not available from the exchange, obtained from two dealers. If bid and asked prices are not available from either the exchange or two dealers, the security is valued by using one of the following methodologies (listed in order of priority): (1) using a bid from the exchange, (2) the mean between the bid and asked price as provided by a single dealer, or (3) a bid from a single dealer.

Shares of a registered investment company that are not traded on an exchange are valued at that investment company’s net asset value per share.

Corporate and government debt securities (of U.S. or foreign issuers) and municipal debt securities, event-linked bonds, loans, mortgage-backed securities, collateralized mortgage obligations, and asset-backed securities are valued at the mean between the “bid” and “asked” prices utilizing evaluated prices obtained from third party pricing services or broker-dealers who may use matrix pricing methods to determine the evaluated prices.

Short-term money market type debt securities with a remaining maturity of sixty days or less are valued at cost adjusted by the amortization of discount or premium to maturity (amortized cost), which approximates market value. Short-term debt securities with a remaining maturity in excess of sixty days are valued at the mean between the “bid” and “asked” prices utilizing evaluated prices obtained from third party pricing services or broker-dealers.

A description of the standard inputs that may generally be considered by the third party pricing vendors in determining their evaluated prices is provided below.


Security Type		Standard inputs generally considered by third-party pricing vendors

Corporate debt, government debt, municipal, mortgage-backed and asset-backed securities		Reported trade data, broker-dealer price quotations, benchmark yields, issuer spreads on comparable securities, the credit quality, yield, maturity, and other appropriate factors.

Loans		Information obtained from market participants regarding reported trade data and broker-dealer price quotations.

Event-linked bonds		Information obtained from market participants regarding reported trade data and broker-dealer price quotations.

31 OPPENHEIMER MAIN STREET FUND

NOTES TO FINANCIAL STATEMENTS Continued

2. Securities Valuation (Continued)

If a market value or price cannot be determined for a security using the methodologies described above, or if, in the “good faith” opinion of the Manager, the market value or price obtained does not constitute a “readily available market quotation,” or a significant event has occurred that would materially affect the value of the security the security is fair valued either (i) by a standardized fair valuation methodology applicable to the security type or the significant event as previously approved by the Valuation Committee and the Fund’s Board or (ii) as determined in good faith by the Manager’s Valuation Committee. The Valuation Committee considers all relevant facts that are reasonably available, through either public information or information available to the Manager, when determining the fair value of a security. Fair value determinations by the Manager are subject to review, approval and ratification by the Fund’s Board at its next regularly scheduled meeting covering the calendar quarter in which the fair valuation was determined. Those fair valuation standardized methodologies include, but are not limited to, valuing securities at the last sale price or initially at cost and subsequently adjusting the value based on: changes in company specific fundamentals, changes in an appropriate securities index, or changes in the value of similar securities which may be further adjusted for any discounts related to security-specific resale restrictions. When possible, such methodologies use observable market inputs such as unadjusted quoted prices of similar securities, observable interest rates, currency rates and yield curves. The methodologies used for valuing securities are not necessarily an indication of the risks associated with investing in those securities nor can it be assured that the Fund can obtain the fair value assigned to a security if it were to sell the security.

To assess the continuing appropriateness of security valuations, the Manager, or its third party service provider who is subject to oversight by the Manager, regularly compares prior day prices, prices on comparable securities, and sale prices to the current day prices and challenges those prices exceeding certain tolerance levels with the third party pricing service or broker source. For those securities valued by fair valuations, whether through a standardized fair valuation methodology or a fair valuation determination, the Valuation Committee reviews and affirms the reasonableness of the valuations based on such methodologies and fair valuation determinations on a regular basis after considering all relevant information that is reasonably available.

Classifications

Each investment asset or liability of the Fund is assigned a level at measurement date based on the significance and source of the inputs to its valuation. Various data inputs are used in determining the value of each of the Fund’s investments as of the reporting period end. These data inputs are categorized in the following hierarchy under applicable financial accounting standards:

1) Level 1-unadjusted quoted prices in active markets for identical assets or liabilities (including securities actively traded on a securities exchange)

2) Level 2-inputs other than unadjusted quoted prices that are observable for the asset or liability (such as unadjusted quoted prices for similar assets and market corroborated inputs such as interest rates, prepayment speeds, credit risks, etc.)

32 OPPENHEIMER MAIN STREET FUND

2. Securities Valuation (Continued)

3) Level 3-significant unobservable inputs (including the Manager’s own judgments about assumptions that market participants would use in pricing the asset or liability).

The inputs used for valuing securities are not necessarily an indication of the risks associated with investing in those securities.

The table below categorizes amounts that are included in the Fund’s Statement of Assets and Liabilities as of August 29, 2014 based on valuation input level:


	Level 1— Unadjusted Quoted Prices		Level 2— Other Significant Observable Inputs		Level 3— Significant Unobservable Inputs		Value

Assets Table
Investments, at Value:
Common Stocks
Consumer Discretionary	$	856,554,017	$	—	$	—	$	856,554,017
Consumer Staples		401,516,281		271,557,550		—		673,073,831
Energy		671,060,551		—		—		671,060,551
Financials		1,302,731,124		—		—		1,302,731,124
Health Care		1,169,338,569		—		—		1,169,338,569
Industrials		766,602,666		—		—		766,602,666
Information Technology		1,438,167,435		—		—		1,438,167,435
Materials		121,452,115		—		—		121,452,115
Telecommunication Services		124,112,580		—		—		124,112,580
Utilities		111,171,162		—		—		111,171,162
Preferred Stock		—		24,897,421		—		24,897,421
Investment Company		82,705,816		—		—		82,705,816

Total Assets	$	7,045,412,316	$	296,454,971	$	—	$	7,341,867,287

Forward currency exchange contracts and futures contracts, if any, are reported at their unrealized appreciation/depreciation at measurement date, which represents the change in the contract’s value from trade date. All additional assets and liabilities included in the above table are reported at their market value at measurement date.

3. Shares of Beneficial Interest

The Fund has authorized an unlimited number of $0.001 par value shares of beneficial interest of each class. Transactions in shares of beneficial interest were as follows:

33 OPPENHEIMER MAIN STREET FUND

NOTES TO FINANCIAL STATEMENTS Continued

3. Shares of Beneficial Interest (Continued)


	Year Ended August 29, 2014						Year Ended August 30, 2013
	Shares			Amount			Shares			Amount

Class A
Sold		6,401,475		$	309,467,062			7,304,054		$	285,427,397
Dividends and/or distributions reinvested		670,830			31,269,321			1,199,774			43,961,194
Redeemed		(12,348,590	)		(595,204,924	)		(17,965,663	)		(706,987,574)

Net decrease		(5,276,285	)	$	(254,468,541	)		(9,461,835	)	$	(377,598,983)



Class B
Sold		114,133		$	5,390,065			163,618		$	6,117,747
Dividends and/or distributions reinvested		—			—			—			—
Redeemed		(1,480,563	)		(68,585,711	)		(2,078,787	)		(78,715,981)

Net decrease		(1,366,430	)	$	(63,195,646	)		(1,915,169	)	$	(72,598,234)



Class C
Sold		1,005,757		$	46,541,449			1,076,878		$	40,966,629
Dividends and/or distributions reinvested		—			—			30,200			1,066,655
Redeemed		(1,923,393	)		(89,028,618	)		(2,437,303	)		(92,450,125)

Net decrease		(917,636	)	$	(42,487,169	)		(1,330,225	)	$	(50,416,841)



Class I
Sold		5,997,348		$	282,983,589			627,883		$	24,005,900
Dividends and/or distributions reinvested		26,824			1,274,371			3,229			118,412
Redeemed		(987,659	)		(47,887,762	)		(36,071	)		(1,459,408)

Net increase		5,036,513		$	236,370,198			595,041		$	22,664,904



Class R¹
Sold		448,740		$	21,251,150			552,113		$	21,072,973
Dividends and/or distributions reinvested		9,939			458,186			17,652			638,131
Redeemed		(706,581	)		(33,383,666	)		(854,727	)		(33,093,617)

Net decrease		(247,902	)	$	(11,674,330	)		(284,962	)	$	(11,382,513)



Class Y
Sold		2,906,362		$	140,110,266			13,990,629		$	553,841,334
Dividends and/or distributions reinvested		181,045			8,442,176			153,123			5,609,777
Redeemed		(7,527,290	)		(355,223,239	)		(3,611,943	)		(143,626,908)

Net increase (decrease)		(4,439,883	)	$	(206,670,797	)		10,531,809		$	415,824,203

1. Effective July 1, 2014, Class N shares were renamed Class R.

34 OPPENHEIMER MAIN STREET FUND

4. Purchases and Sales of Securities

The aggregate cost of purchases and proceeds from sales of securities, other than short-term obligations and investments in IMMF, for the year ended August 29, 2014 were as follows:


	Purchases		Sales

Investment securities		$3,539,641,426		$3,910,474,805

5. Fees and Other Transactions with Affiliates

Management Fees. Under the investment advisory agreement, the Fund pays the Manager a management fee based on the daily net assets of the Fund at an annual rate as shown in the following table:


Fee Schedule Through October 31, 2013

Up to $200 million	0.65	%
Next $150 million	0.60
Next $150 million	0.55
Over $500 million	0.45


Fee Schedule Effective November 1, 2013

Up to $200 million	0.65	%
Next $150 million	0.60
Next $150 million	0.55
Next $9.5 billion	0.45
Over $10 billion	0.43

Sub-Adviser Fees. The Manager has retained the Sub-Adviser to provide the day-to-day portfolio management of the Fund. Under the Sub-Advisory Agreement, the Manager pays the Sub-Adviser an annual fee in monthly installments, equal to a percentage of the investment management fee collected by the Manager from the Fund, which shall be calculated after any investment management fee waivers. The fee paid to the Sub-Adviser is paid by the Manager, not by the Fund.

Transfer Agent Fees. OFI Global (the “Transfer Agent”) serves as the transfer and shareholder servicing agent for the Fund. The Fund pays the Transfer Agent a fee based on annual net assets. Fees incurred and average net assets for each class with respect to these services are detailed in the Statement of Operations and Financial Highlights, respectively.

Sub-Transfer Agent Fees. The Transfer Agent has retained Shareholder Services, Inc., a wholly-owned subsidiary of OFI (the “Sub-Transfer Agent”), to provide the day-to-day transfer agent and shareholder servicing of the Fund. Under the Sub-Transfer Agency Agreement, the Transfer Agent pays the Sub-Transfer Agent an annual fee in monthly installments, equal to a percentage of the transfer agent fee collected by the Transfer Agent from the Fund, which shall be calculated after any applicable fee waivers. The fee paid to the Sub-Transfer Agent is paid by the Transfer Agent, not by the Fund.

Distribution and Service Plan (12b-1) Fees. Under its General Distributor’s Agreement with the Fund, OppenheimerFunds Distributor, Inc. (the “Distributor”) acts as the Fund’s principal underwriter in the continuous public offering of the Fund’s classes of shares.

Service Plan for Class A Shares. The Fund has adopted a Service Plan (the “Plan”) for Class A shares under Rule 12b-1 of the Investment Company Act of 1940. Under the Plan, the Fund reimburses the Distributor for a portion of its costs incurred for services provided to

35 OPPENHEIMER MAIN STREET FUND

NOTES TO FINANCIAL STATEMENTS Continued

5. Fees and Other Transactions with Affiliates (Continued)

accounts that hold Class A shares. Reimbursement is made periodically at an annual rate of up to 0.25% of the daily net assets of Class A shares of the Fund. The Distributor currently uses all of those fees to pay dealers, brokers, banks and other financial institutions periodically for providing personal service and maintenance of accounts of their customers that hold Class A shares. Any unreimbursed expenses the Distributor incurs with respect to Class A shares in any fiscal year cannot be recovered in subsequent periods. Fees incurred by the Fund under the Plan are detailed in the Statement of Operations.

Distribution and Service Plans for Class B, Class C and Class R Shares. The Fund has adopted Distribution and Service Plans (the “Plans”) for Class B, Class C and Class R shares under Rule 12b-1 of the Investment Company Act of 1940 to compensate the Distributor for distributing those share classes, maintaining accounts and providing shareholder services. Under the Plans, the Fund pays the Distributor an annual asset-based sales charge of 0.75% on Class B and Class C shares daily net assets and 0.25% on Class R shares daily net assets. The Fund also pays a service fee under the Plans at an annual rate of 0.25% of daily net assets. The Plans continue in effect from year to year only if the Fund’s Board of Trustees vote annually to approve its continuance at an in person meeting called for that purpose. Fees incurred by the Fund under the Plans are detailed in the Statement of Operations.

Sales Charges. Front-end sales charges and contingent deferred sales charges (“CDSC”) do not represent expenses of the Fund. They are deducted from the proceeds of sales of Fund shares prior to investment or from redemption proceeds prior to remittance, as applicable. The sales charges retained by the Distributor from the sale of shares and the CDSC retained by the Distributor on the redemption of shares is shown in the following table for the period indicated.


Year Ended	Class A Front-End Sales Charges Retained by Distributor		Class A Contingent Deferred Sales Charges Retained by Distributor		Class B Contingent Deferred Sales Charges Retained by Distributor		Class C Contingent Deferred Sales Charges Retained by Distributor		Class R Contingent Deferred Sales Charges Retained by Distributor

August 29, 2014		$1,109,095		$8,781		$159,619		$21,518		$487

Waivers and Reimbursements of Expenses. The Manager will waive fees and/or reimburse Fund expenses in an amount equal to the indirect management fees incurred through the Fund’s investment in IMMF. During the year ended August 29, 2014, the Manager waived fees and/or reimbursed the Fund $116,704 for IMMF management fees.

The Transfer Agent has contractually agreed to limit transfer and shareholder servicing agent fees for Classes B, C, R and Y shares to 0.35% of average annual net assets per class and for Class A shares to 0.30% of average annual net assets of the class. The limit was removed on December 27, 2013.

During the year ended August 29, 2014, the Transfer Agent waived transfer and shareholder servicing agent fees as follows:

36 OPPENHEIMER MAIN STREET FUND

5. Fees and Other Transactions with Affiliates (Continued)


Class B	$	25,511
Class C		984
Class R		502
Class Y		806

These undertakings may be modified or terminated as set forth according to the terms in the prospectus.

6. Pending Litigation

In 2009, seven class action lawsuits were filed in the U.S. District Court for the District of Colorado against OppenheimerFunds, Inc. (“OFI”), OppenheimerFunds Distributor, Inc., the Fund’s principal underwriter and distributor (the “Distributor”), and certain funds (but not including the Fund) advised by OFI Global Asset Management, Inc. and distributed by the Distributor (the “Defendant Funds”). The lawsuits also named as defendants certain officers and current and former trustees of the respective Defendant Funds. The lawsuits raised claims under federal securities law and alleged, among other things, that the disclosure documents of the respective Defendant Funds contained misrepresentations and omissions and that the respective Defendant Funds’ investment policies were not followed. The plaintiffs in these actions sought unspecified damages, equitable relief and awards of attorneys’ fees and litigation expenses. The Defendant Funds’ Boards of Trustees also engaged counsel to represent the Funds and the present and former Independent Trustees named in those suits. On March 5, 2014, the parties in six of these lawsuits executed stipulations and agreements of settlement resolving those actions. On July 31, 2014, the court entered an order and final judgment approving the settlements as fair, reasonable and adequate. The settlements do not resolve a seventh outstanding lawsuit relating to Oppenheimer Rochester California Municipal Fund.

Other class action and individual lawsuits have been filed since 2008 in various state and federal courts against OFI and certain of its affiliates by investors seeking to recover investments they allegedly lost as a result of the “Ponzi” scheme run by Bernard L. Madoff and his firm, Bernard L. Madoff Investment Securities, LLC (“BLMIS”). Plaintiffs in these suits allege that they suffered losses as a result of their investments in several funds managed by an affiliate of OFI and assert a variety of claims, including breach of fiduciary duty, fraud, negligent misrepresentation, unjust enrichment, and violation of federal and state securities laws and regulations, among others. They seek unspecified damages, equitable relief and awards of attorneys’ fees and litigation expenses. Neither the Distributor, nor any of the Oppenheimer mutual funds, their independent trustees or directors are named as defendants in these lawsuits. None of the Oppenheimer mutual funds invested in any funds or accounts managed by Madoff or BLMIS. On February 28, 2011, a stipulation of partial settlement of three groups of consolidated putative class action lawsuits relating to these matters was filed in the U.S. District Court for the Southern District of New York. On August 19, 2011, the court entered an order and final judgment approving the settlement as fair, reasonable and

37 OPPENHEIMER MAIN STREET FUND

NOTES TO FINANCIAL STATEMENTS Continued

6. Pending Litigation (Continued)

adequate. In September 2011, certain parties filed notices of appeal from the court’s order approving the settlement. In June 2014, the appellate court affirmed the lower court’s order approving the settlement. Certain parties subsequently filed a petition for certiorari before the U.S. Supreme Court further challenging the settlement approval order. The settlement does not resolve other outstanding lawsuits against OFI and its affiliates relating to BLMIS.

OFI believes the lawsuits and appeals described above are without legal merit and, with the exception of actions it has settled, is defending against them vigorously. While it is premature to render any opinion as to the outcome in these lawsuits, or whether any costs that the Defendant Funds may bear in defending the suits might not be reimbursed by insurance, OFI believes that these suits should not impair the ability of OFI or the Distributor to perform their respective duties to the Fund, and that the outcome of all of the suits together should not have any material effect on the operations of any of the Oppenheimer mutual funds.

38 OPPENHEIMER MAIN STREET FUND

REPORTOF INDEPENDENT REGISTERED PUBLIC

ACCOUNTING FIRM

The Board of Trustees and Shareholders of Oppenheimer Main Street Fund:

We have audited the accompanying statement of assets and liabilities of Oppenheimer Main Street Fund, a series of Oppenheimer Main Street Funds, including the statement of investments, as of August 29, 2014, and the related statement of operations for the year then ended, the statements of changes in net assets for each of the years in the two-year period then ended, and the financial highlights for each of the years or periods in the five-year period then ended. These financial statements and financial highlights are the responsibility of the Fund’s management. Our responsibility is to express an opinion on these financial statements and financial highlights based on our audits.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements and financial highlights are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements. Our procedures included confirmation of securities owned as of August 29, 2014, by correspondence with the custodian, transfer agent and brokers, or by other appropriate auditing procedures where replies from brokers were not received. An audit also includes assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

In our opinion, the financial statements and financial highlights referred to above present fairly, in all material respects, the financial position of Oppenheimer Main Street Fund as of August 29, 2014, the results of its operations for the year then ended, the changes in its net assets for each of the years in the two-year period then ended, and the financial highlights for each of the years or periods in the five-year period then ended, in conformity with U.S. generally accepted accounting principles.

KPMG LLP

Denver, Colorado

October 14, 2014

39 OPPENHEIMER MAIN STREET FUND

FEDERAL INCOME TAX INFORMATION Unaudited

In early 2014, if applicable, shareholders of record received information regarding all dividends and distributions paid to them by the Fund during calendar year 2013.

Dividends, if any, paid by the Fund during the fiscal year ended August 29, 2014 which are not designated as capital gain distributions should be multiplied by the maximum amount allowable but not less than 100% to arrive at the amount eligible for the corporate dividend-received deduction.

A portion, if any, of the dividends paid by the Fund during the fiscal year ended August 29, 2014 which are not designated as capital gain distributions are eligible for lower individual income tax rates to the extent that the Fund has received qualified dividend income as stipulated by recent tax legislation. The maximum amount allowable but not less than $100,573,088 of the Fund’s fiscal year taxable income may be eligible for the lower individual income tax rates. In early 2014, shareholders of record received information regarding the percentage of distributions that are eligible for lower individual income tax rates.

Recent tax legislation allows a regulated investment company to designate distributions not designated as capital gain distributions, as either interest related dividends or short-term capital gain dividends, both of which are exempt from the U.S. withholding tax applicable to non U.S. taxpayers. For the fiscal year ended August 29, 2014, the maximum amount allowable but not less than $36,202 of the ordinary distributions to be paid by the Fund qualifies as an interest related dividend.

The foregoing information is presented to assist shareholders in reporting distributions received from the Fund to the Internal Revenue Service. Because of the complexity of the federal regulations which may affect your individual tax return and the many variations in state and local tax regulations, we recommend that you consult your tax advisor for specific guidance.

40 OPPENHEIMER MAIN STREET FUND

BOARD APPROVAL OF THE FUND’S INVESTMENT

ADVISORY AGREEMENT Unaudited

The Fund has entered into an investment advisory agreement with OFI Global Asset Management, Inc. (“OFI Global” or the “Adviser”), a wholly-owned subsidiary of OppenheimerFunds, Inc. (“OFI” or the “Sub-Adviser”) (“OFI Global” and “OFI” together the “Managers”) and OFI Global has entered into a sub-advisory agreement with OFI whereby OFI provides investment sub-advisory services to the Fund (collectively, the “Agreements”). Each year, the Board of Trustees (the “Board”), including a majority of the independent Trustees, is required to determine whether to renew the Agreements. The Investment Company Act of 1940, as amended, requires that the Board request and evaluate, and that the Managers provide, such information as may be reasonably necessary to evaluate the terms of the Agreements. The Board employs an independent consultant to prepare a report that provides information, including comparative information that the Board requests for that purpose. In addition to in-person meetings focused on this evaluation, the Board receives information throughout the year regarding Fund services, fees, expenses and performance.

The Adviser, Sub-Adviser and the independent consultant provided information to the Board on the following factors: (i) the nature, quality and extent of the Managers’ services, (ii) the investment performance of the Fund and the Managers, (iii) the fees and expenses of the Fund, including comparative expense information, (iv) the profitability of the Managers and their affiliates, including an analysis of the cost of providing services, (v) whether economies of scale are realized as the Fund grows and whether fee levels reflect these economies of scale for Fund investors and (vi) other benefits to the Managers from their relationship with the Fund. The Board was aware that there are alternatives to retaining the Managers.

Outlined below is a summary of the principal information considered by the Board as well as the Board’s conclusions.

Nature, Quality and Extent of Services. The Board considered information about the nature, quality and extent of the services provided to the Fund and information regarding the Managers’ key personnel who provide such services. The Sub-Adviser’s duties include providing the Fund with the services of the portfolio managers and the Sub-Adviser’s investment team, who provide research, analysis and other advisory services in regard to the Fund’s investments; securities trading services; oversight of third-party service providers; monitoring compliance with applicable Fund policies and procedures and adherence to the Fund’s investment restrictions; and risk management. The Managers are responsible for providing certain administrative services to the Fund as well. Those services include providing and supervising all administrative and clerical personnel who are necessary in order to provide effective corporate administration for the Fund; compiling and maintaining records with respect to the Fund’s operations; preparing and filing reports required by the Securities and Exchange Commission; preparing periodic reports regarding the operations of the Fund for its shareholders; preparing proxy materials for shareholder meetings; and preparing the registration statements required by Federal and state securities laws for the sale of the Fund’s shares. The Managers also provide the Fund with office space, facilities and equipment.

The Board also considered the quality of the services provided and the quality of the Managers’ resources that are available to the Fund. The Board took account of the fact that the Sub-Adviser has had over fifty years of experience as an investment adviser and that its assets under management rank it among the top mutual fund managers in the United States.

41 OPPENHEIMER MAIN STREET FUND

BOARD APPROVAL OF THE FUND’S INVESTMENT

ADVISORY AGREEMENT Unaudited / Continued

The Board evaluated the Sub-Adviser’s advisory, administrative, accounting, legal, compliance services and risk management, and information the Board has received regarding the experience and professional qualifications of the Managers’ key personnel and the size and functions of its staff. In its evaluation of the quality of the portfolio management services provided, the Board considered the experience of Manind “Mani” Govil, Benjamin Ram, and Paul Larson, the portfolio managers for the Fund, and the Sub-Adviser’s investment team and analysts. The Board members also considered the totality of their experiences with the Managers as directors or trustees of the Fund and other funds advised by the Managers. The Board considered information regarding the quality of services provided by affiliates of the Managers, which its members have become knowledgeable about in connection with the renewal of the Fund’s service agreements. The Board concluded, in light of the Managers’ experience, reputation, personnel, operations and resources that the Fund benefits from the services provided under the Agreements.

Investment Performance of the Manager, the Sub-Adviser and the Fund. Throughout the year, the Manager and the Sub-Adviser provided information on the investment performance of the Fund, the Manager and the Sub-Adviser, including comparative performance information. The Board also reviewed information, prepared by the Manager, the Sub-Adviser and the independent consultant, comparing the Fund’s historical performance to its benchmark and to the performance of other retail large blend funds. The Board considered that the Fund outperformed its category median for the three- and five-year periods, although it underperformed its category median for the one- and ten-year periods. The Board also considered that the Fund’s performance for the three- and five-year periods was in the second quintile of its category and in the third quintile for the one- and ten-year periods. The Board noted that the Fund had changed portfolio managers effective May 19, 2009 and that the Fund’s three- and five-year rankings are evidence of the improved performance the portfolio managers have delivered for the Fund.

Costs of Services by the Manager. The Board reviewed the fees paid to the Manager and the Sub-Adviser and the other expenses borne by the Fund. The Board noted that the Manager, not the Fund, pays the Sub-Adviser’s fee under the sub-advisory agreement. The Board also considered the comparability of the fees charged and the services provided to the Fund to the fees and services for other clients or accounts advised by the Manager. The independent consultant provided comparative data in regard to the fees and expenses of the Fund and other retail large blend funds with comparable asset levels and distribution features. The Fund’s contractual management fees and total expenses were lower than their respective peer group medians and category medians and ranked in the first quintile of their respective categories. Within the average net asset range of $5 billion to $10 billion, the Fund’s effective management fee rate was lower than its peer group median and category median.

Economies of Scale and Profits Realized by the Manager and Sub-Adviser. The Board considered information regarding the Managers’ costs in serving as the Fund’s investment adviser and sub-adviser, including the costs associated with the personnel and systems necessary to manage the Fund, and information regarding the Managers’ profitability from their relationship with the Fund. The Board reviewed whether the Managers may realize economies of scale in managing and supporting the Fund. The Board noted that the Fund

42 OPPENHEIMER MAIN STREET FUND

currently has management fee breakpoints, which are intended to share with Fund shareholders economies of scale that may exist as the Fund’s assets grow and which are appropriate given the Fund’s current size.

Other Benefits to the Managers. In addition to considering the profits realized by the Managers, the Board considered information that was provided regarding the direct and indirect benefits the Managers receive as a result of their relationship with the Fund, including compensation paid to the Managers’ affiliates and research provided to the Adviser in connection with permissible brokerage arrangements (soft dollar arrangements).The Board also considered that the Managers must be able to pay and retain experienced professional personnel at competitive rates to provide quality services to the Fund.

Conclusions. These factors were also considered by the independent Trustees meeting separately from the full Board, assisted by experienced counsel to the Fund and to the independent Trustees. Fund counsel and the independent Trustees’ counsel are independent of the Managers within the meaning and intent of the Securities and Exchange Commission Rules.

Based on its review of the information it received and its evaluations described above, the Board, including a majority of the independent Trustees, decided to continue the Agreements through August 31, 2015. In arriving at its decision, the Board did not identify any factor or factors as being more important than others, but considered all of the above information, and considered the terms and conditions of the Agreements, including the management fees, in light of all the surrounding circumstances.

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PORTFOLIO PROXY VOTING POLICIES AND PROCEDURES;

UPDATES TO STATEMENTS OF INVESTMENTS Unaudited

The Fund has adopted Portfolio Proxy Voting Policies and Procedures under which the Fund votes proxies relating to securities (“portfolio proxies”) held by the Fund. A description of the Fund’s Portfolio Proxy Voting Policies and Procedures is available (i) without charge, upon request, by calling the Fund toll-free at 1.800.CALL OPP (225.5677), (ii) on the Fund’s website at oppenheimerfunds.com, and (iii) on the SEC’s website at www.sec.gov. In addition, the Fund is required to file Form N-PX, with its complete proxy voting record for the 12 months ended June 30th, no later than August 31st of each year. The Fund’s voting record is available (i) without charge, upon request, by calling the Fund toll-free at 1.800.CALL OPP (225.5677), and (ii) in the Form N-PX filing on the SEC’s website at www.sec.gov.

The Fund files its complete schedule of portfolio holdings with the SEC for the first quarter and the third quarter of each fiscal year on Form N-Q. The Fund’s Form N-Q filings are available on the SEC’s website at www.sec.gov. Those forms may be reviewed and copied at the SEC’s Public Reference Room in Washington, D.C. Information on the operation of the Public Reference Room may be obtained by calling 1-800-SEC-0330.

Householding—Delivery of Shareholder Documents

This is to inform you about OppenheimerFunds’ “householding” policy. If more than one member of your household maintains an account in a particular fund, OppenheimerFunds will mail only one copy of the fund’s prospectus (or, if available, the fund’s summary prospectus), annual and semiannual report and privacy policy. The consolidation of these mailings, called householding, benefits your fund through reduced mailing expense, and benefits you by reducing the volume of mail you receive from OppenheimerFunds. Householding does not affect the delivery of your account statements.

Please note that we will continue to household these mailings for as long as you remain an OppenheimerFunds shareholder, unless you request otherwise. If you prefer to receive multiple copies of these materials, please call us at 1.800.CALL-OPP (225-5677). You may also notify us in writing or via email. We will begin sending you individual copies of the prospectus (or, if available, the summary prospectus), reports and privacy policy within 30 days of receiving your request to stop householding.

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TRUSTEES AND OFFICERS (AS OF 9/30/14) Unaudited


Name, Position(s) Held with the Fund, Length of Service, Year of Birth		Principal Occupation(s) During the Past 5 Years; Other Trusteeships/Directorships Held; Number of Portfolios in the Fund Complex Currently Overseen

INDEPENDENT TRUSTEES		The address of each Trustee in the chart below is 6803 S. Tucson Way, Centennial, Colorado 80112-3924. Each Trustee serves for an indefinite term, or until his or her resignation, retirement, death or removal.

Sam Freedman, Chairman of the Board of Trustees (since 2012) and Trustee (since 1996) Year of Birth: 1940		Director of Colorado UpLIFT (charitable organization) (since September 1984). Mr. Freedman held several positions with the Sub-Adviser and with subsidiary or affiliated companies of the Sub-Adviser (until October 1994). Oversees 39 portfolios in the OppenheimerFunds complex. Mr. Freedman has served on the Boards of certain Oppenheimer funds since 1996, during which time he has become familiar with the Fund’s (and other Oppenheimer funds’) financial, accounting, regulatory and investment matters and has contributed to the Boards’ deliberations.

Jon S. Fossel, Trustee (since 1990) Year of Birth: 1942		Chairman of the Board (2006-December 2011) and Director (June 2002-December 2011) of UNUMProvident (insurance company); Director of Northwestern Energy Corp. (public utility corporation) (November 2004-December 2009); Director of P.R. Pharmaceuticals (October 1999-October 2003); Director of Rocky Mountain Elk Foundation (non-profit organization) (February 1998-February 2003 and February 2005-February 2007); Chairman and Director (until October 1996) and President and Chief Executive Officer (until October 1995) of the Sub-Adviser; President, Chief Executive Officer and Director of the following: Oppenheimer Acquisition Corp. (“OAC”) (parent holding company of the Sub-Adviser), Shareholders Services, Inc. and Shareholder Financial Services, Inc. (until October 1995). Oversees 39 portfolios in the OppenheimerFunds complex. Mr. Fossel has served on the Boards of certain Oppenheimer funds since 1990, during which time he has become familiar with the Fund’s (and other Oppenheimer funds’) financial, accounting, regulatory and investment matters and has contributed to the Boards’ deliberations.

Richard F. Grabish, Trustee (since 2012) Year of Birth: 1948		Formerly Senior Vice President and Assistant Director of Sales and Marketing (March 1997-December 2007), Director (March 1987-December 2007) and Manager of Private Client Services (June 1985-June 2005) of A.G. Edwards & Sons, Inc. (broker/dealer and investment firm); Chairman and Chief Executive Officer of A.G. Edwards Trust Company, FSB (March 2001-December 2007); President and Vice Chairman of A.G. Edwards Trust Company, FSB (investment adviser) (April 1987-March 2001); President of A.G. Edwards Trust Company, FSB (investment adviser) (June 2005-December 2007). Oversees 39 portfolios in the OppenheimerFunds complex. Mr. Grabish has served on the Boards of certain Oppenheimer funds since 2001, during which time he has become familiar with the Fund’s (and other Oppenheimer funds’) financial, accounting, regulatory and investment matters and has contributed to the Boards’ deliberations.

Beverly L. Hamilton, Trustee (since 2002) Year of Birth: 1946		Trustee of Monterey Institute for International Studies (educational organization) (since February 2000); Board Member of Middlebury College (educational organization) (December 2005-June 2011); Chairman (since 2010) of American Funds’ Emerging Markets Growth Fund, Inc. (mutual fund);

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TRUSTEES AND OFFICERS Unaudited / Continued


Beverly L. Hamilton, Continued		Director of The California Endowment (philanthropic organization) (April 2002-April 2008); Director (February 2002-2005) and Chairman of Trustees (2006-2007) of the Community Hospital of Monterey Peninsula; Director (October 1991-2005); Vice Chairman (2006-2009) of American Funds’ Emerging Markets Growth Fund, Inc. (mutual fund); President of ARCO Investment Management Company (February 1991-April 2000); Member of the investment committees of The Rockefeller Foundation (2001-2006) and The University of Michigan (since 2000); Advisor at Credit Suisse First Boston’s Sprout venture capital unit (venture capital fund) (1994-January 2005); Trustee of MassMutual Institutional Funds (investment company) (1996-June 2004); Trustee of MML Series Investment Fund (investment company) (April 1989-June 2004); Member of the investment committee of Hartford Hospital (2000-2003); and Advisor to Unilever (Holland) pension fund (2000-2003). Oversees 39 portfolios in the OppenheimerFunds complex. Ms. Hamilton has served on the Boards of certain Oppenheimer funds since 2002, during which time she has become familiar with the Fund’s (and other Oppenheimer funds’) financial, accounting, regulatory and investment matters and has contributed to the Boards’ deliberations.

Victoria J. Herget, Trustee (since 2012) Year of Birth: 1951		Independent Director of the First American Funds (mutual fund family) (2003-2011); former Managing Director (1993-2001), Principal (1985-1993), Vice President (1978-1985) and Assistant Vice President (1973-1978) of Zurich Scudder Investments (and its predecessor firms); Board Chair (2008-Present) and Director (2004-Present), United Educators (insurance company); Trustee (1992-2007), Chair of the Board of Trustees (1999-2007), Investment Committee Chair (1994-1999) and Investment Committee member (2007-2010) of Wellesley College; Trustee (since 2000) and Chair (since 2010), Newberry Library; Trustee, Mather LifeWays (since 2001); Trustee, BoardSource (2006-2009) and Chicago City Day School (1994-2005). Oversees 39 portfolios in the OppenheimerFunds complex. Ms. Herget has served on the Boards of certain Oppenheimer funds since 2012, during which time she has become familiar with the Fund’s (and other Oppenheimer funds’) financial, accounting, regulatory and investment matters and has contributed to the Boards’ deliberations.

Robert J. Malone, Trustee (since 2002) Year of Birth: 1944		Chairman of the Board (since 2012) and Director (since August 2005) of Jones International University (educational organization) (since August 2005); Chairman, Chief Executive Officer and Director of Steele Street Bank Trust (commercial banking) (since August 2003); Trustee of the Gallagher Family Foundation (non-profit organization) (since 2000); Board of Directors of Opera Colorado Foundation (non-profit organization) (2008-2012); Director of Colorado UpLIFT (charitable organization) (1986-2010); Director of Jones Knowledge, Inc. (2006-2010); Former Chairman of U.S. Bank-Colorado (subsidiary of U.S. Bancorp and formerly Colorado National Bank) (July 1996-April 1999); Director of Commercial Assets, Inc. (real estate investment trust) (1993-2000); Director of U.S. Exploration, Inc. (oil and gas exploration) (1997-February 2004); Chairman of the Board (1991-1994) and Trustee (1985-1994) of Regis University; and Chairman of the Board (1990-1991 and Trustee (1984-1999) of Young Presidents Organization. Oversees 39 portfolios in the OppenheimerFunds complex. Mr. Malone has served on the Boards of certain Oppenheimer funds since 2002, during which time he has become familiar with the Fund’s (and other Oppenheimer funds’) financial, accounting, regulatory and investment matters and has contributed to the Boards’ deliberations.

46 OPPENHEIMER MAIN STREET FUND


F. William Marshall, Jr., Trustee (since 2001) Year of Birth: 1942		Trustee Emeritus of Worcester Polytech Institute (WPI) (private university) (since 2009); Trustee of MassMutual Select Funds (formerly MassMutual Institutional Funds) (investment company) (since 1996), MML Series Investment Fund (investment company) (since 1996) and Mass Mutual Premier Funds (investment company) (since January 2012); President and Treasurer of the SIS Fund (private charitable fund) (January 1999 – March 2011); Former Trustee of WPI (1985-2008); Former Chairman of the Board (2004-2006) and Former Chairman of the Investment Committee of WPI (1994-2008); Chairman of SIS & Family Bank, F.S.B. (formerly SIS Bank) (commercial bank) (January 1999-July 1999); Executive Vice President of Peoples Heritage Financial Group, Inc. (commercial bank) (January 1999-July 1999); and Former President and Chief Executive Officer of SIS Bancorp. (1993-1999). Oversees 43 portfolios in the OppenheimerFunds complex. Mr. Marshall has served on the Boards of certain Oppenheimer funds since 2000, during which time he has become familiar with the Fund’s (and other Oppenheimer funds’) financial, accounting, regulatory and investment matters and has contributed to the Boards’ deliberations.

Karen L. Stuckey, Trustee (since 2012) Year of Birth: 1953		Partner (1990-2012) of PricewaterhouseCoopers LLP (held various positions 1975-1990); Emeritus Trustee (since 2006), Trustee (1992-2006) and member of Executive, Nominating and Audit Committees and Chair of Finance Committee of Lehigh University; and member, Women’s Investment Management Forum since inception. Oversees 39 portfolios in the OppenheimerFunds complex. Ms. Stuckey has served on the Boards of certain Oppenheimer funds since 2012, during which time she has become familiar with the Fund’s (and other Oppenheimer funds’) financial, accounting, regulatory and investment matters and has contributed to the Boards’ deliberations.

James D. Vaughn, Trustee (since 2012) Year of Birth: 1945		Retired; former managing partner (1994-2001) of Denver office of Deloitte & Touche LLP, (held various positions 1969-1993); Trustee and Chairman of the Audit Committee of Schroder Funds (2003-2012); Board member and Chairman of Audit Committee of AMG National Trust Bank (since 2005); Trustee and Investment Committee member, University of South Dakota Foundation (since 1996); Board member, Audit Committee Member and past Board Chair, Junior Achievement (since 1993); former Board member, Mile High United Way, Boys and Girls Clubs, Boy Scouts, Colorado Business Committee for the Arts, Economic Club of Colorado and Metro Denver Network. Oversees 39 portfolios in the OppenheimerFunds complex. Mr. Vaughn has served on the Boards of certain Oppenheimer funds since 2012, during which time he has become familiar with the Fund’s (and other Oppenheimer funds’) financial, accounting, regulatory and investment matters and has contributed to the Boards’ deliberations.


INTERESTED TRUSTEE AND OFFICER		Mr. Glavin is an “Interested Trustee” because he is affiliated with the Manager and the Sub-Adviser by virtue of his positions as director of the Sub-Adviser, and as a shareholder of the Sub-Adviser’s parent company. As a Trustee, he serves for an indefinite term, or until his resignation, retirement, death or removal. Mr. Glavin’s address is 225 Liberty Street, 11th Floor, New York, New York 10281-1008.

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TRUSTEES AND OFFICERS Unaudited / Continued


William F. Glavin, Jr., Trustee (since 2009) Year of Birth: 1958		Chairman of the Sub-Adviser (since July 2014 and December 2009-December 2012) and Director of the Sub-Adviser (since January 2009); Chairman, Director and Chief Executive Officer (January 2013-June 2014) of the Manager; President of the Manager (January 2013-May 2013); Chief Executive Officer (January 2009-December 2012); President of the Sub-Adviser (May 2009-December 2012); Management Director (June 2009-June 2014), President (December 2009-June 2014) and Chief Executive Officer (January 2011-June 2014) of Oppenheimer Acquisition Corp. (“OAC”) (the Sub-Adviser’s parent holding company); Director of Oppenheimer Real Asset Management, Inc. (March 2010-June 2014); Executive Vice President (March 2006-February 2009) and Chief Operating Officer (July 2007-February 2009) of Massachusetts Mutual Life Insurance Company (OAC’s parent company); Director (May 2004-March 2006) and Chief Operating Officer and Chief Compliance Officer (May 2004-January 2005), President (January 2005-March 2006) and Chief Executive Officer (June 2005-March 2006) of Babson Capital Management LLC; Director (March 2005-March 2006), President (May 2003-March 2006) and Chief Compliance Officer (July 2005-March 2006) of Babson Capital Securities, Inc. (a brokerdealer); President (May 2003-March 2006) of Babson Investment Company, Inc.; Director (May 2004-August 2006) of Babson Capital Europe Limited; Director (May 2004-October 2006) of Babson Capital Guernsey Limited; Director (May 2004-March 2006) of Babson Capital Management LLC; Non-Executive Director (March 2005-March 2007) of Baring Asset Management Limited; Director (February 2005-June 2006) Baring Pension Trustees Limited; Director and Treasurer (December 2003-November 2006) of Charter Oak Capital Management, Inc.; Director (May 2006-September 2006) of C.M. Benefit Insurance Company; Director (May 2008-June 2009) and Executive Vice President (June 2007-July 2009) of C.M. Life Insurance Company; President (March 2006-May 2007) of MassMutual Assignment Company; Director (January 2005-December 2006), Deputy Chairman (March 2005-December 2006) and President (February 2005-March 2005) of MassMutual Holdings (Bermuda) Limited; Director (May 2008-June 2009) and Executive Vice President (June 2007-July 2009) of MML Bay State Life Insurance Company; Chief Executive Officer and President (April 2007-January 2009) of MML Distributors, LLC; and Chairman (March 2006-December 2008) and Chief Executive Officer (May 2007-December 2008) of MML Investors Services, Inc. An officer of 91 portfolios in the OppenheimerFunds complex. Mr. Glavin has served on the Boards of certain Oppenheimer funds since December 2009, during which time he has become familiar with the Fund’s (and other Oppenheimer funds’) financial, accounting, regulatory and investment matters and has contributed to the Boards’ deliberations.


OTHER OFFICERS OF THE FUND		The addresses of the Officers in the chart below are as follows: for Messrs. Govil, Ram, Larson, Steinmetz, Gabinet, Mss. Sexton and Picciotto, 225 Liberty Street, New York, New York 10281-1008, for Mr. Wixted, 6803 S. Tucson Way, Centennial, Colorado 80112-3924. Each Officer serves for an indefinite term or until his or her resignation, retirement, death or removal.

Manind Govil, Vice President (since 2009) Year of Birth: 1969		Senior Vice President, the Main Street Team Leader and a portfolio manager of the Sub-Adviser (since May 2009). Portfolio manager with RS Investment Management Co. LLC (October 2006-March 2009). Head of equity investments at The Guardian Life Insurance Company of America (August 2005-October 2006) when Guardian Life Insurance acquired an interest in RS

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Manind Govil, Continued		Investment Management Co. LLC. Lead portfolio manager - large cap blend/core equity, co-head of equities and head of equity research (2001-July 2005), and was lead portfolio manager - core equity (April 1996-July 2005), at Mercantile Capital Advisers, Inc. A portfolio manager and officer of other portfolios in the OppenheimerFunds complex.

Benjamin Ram, Vice President (since 2009) Year of Birth: 1972		Vice President of the Sub-Adviser (since May 2009); Senior Portfolio Manager of the Sub-Adviser (since January 2011) and Portfolio Manager of the Sub-Adviser (May 2009-December 2010). Sector manager for financial investments and a co portfolio manager for mid-cap portfolios with the RS Core Equity Team of RS Investment Management Co. LLC (October 2006-May 2009). Portfolio Manager of Mid Cap Strategies, Sector Manager Financials at The Guardian Life Insurance Company of America (January 2006-October 2006) when Guardian Life Insurance acquired an interest in RS Investment Management Co. LLC. Financial analyst (2003-2005), and co-portfolio manager (2005-2006) at Mercantile Capital Advisers, Inc.; bank analyst at Legg Mason Securities (2000-2003) and a senior financial analyst at the CitiFinancial division of Citigroup, Inc. (1997-2000). A portfolio manager and officer of other portfolios in the OppenheimerFunds complex.

Paul Larson, Vice President (since 2014) Year of Birth: 1971		Vice President of the Sub-Adviser (since January 2013). Prior to joining the Sub-Adviser, a portfolio manager and Chief Equity Strategist at Morningstar. He was previously an analyst at Morningstar covering the energy sector and oversaw the firm’s natural resources analysts. Prior to joining Morningstar in 2002, an analyst with The Motley Fool. A portfolio manager and officer of other portfolios in the OppenheimerFunds complex.

Arthur P. Steinmetz, President and Principal Executive Officer (since 2014) Year of Birth: 1958		CEO and Chairman of the Manager (since July 2014), President of the Manager (since May 2013), a Director of the Manager (since January 2013), Director of the Sub-Adviser (since July 2014), President, Management Director and CEO of Oppenheimer Acquisition Corp. (the Sub-Adviser’s parent holding company) (since July 2014), and President and Director of OFI SteelPath, Inc. (since January 2013). Chief Investment Officer of the OppenheimerFunds advisory entities from (January 2013-December 2013); Executive Vice President of the Manager (January 2013-May 2013); Chief Investment Officer of the Sub-Adviser (October 2010-December 2012); Chief Investment Officer, Fixed-Income, of the Sub-Adviser (April 2009-October 2010); Executive Vice President of the Sub-Adviser (October 2009-December 2012); Director of Fixed Income of the Sub-Adviser (January 2009-April 2009); and a Senior Vice President of the Sub-Adviser (March 1993-September 2009). An officer of 91 portfolios in the OppenheimerFunds complex.

Arthur S. Gabinet, Secretary and Chief Legal Officer (since 2011) Year of Birth: 1958		Executive Vice President, Secretary and General Counsel of the Manager (since January 2013); General Counsel OFI SteelPath, Inc. (since January 2013); Executive Vice President (May 2010-December 2012) and General Counsel (since January 2011) of the Sub-Adviser; General Counsel of the Distributor (since January 2011); General Counsel of Centennial Asset Management Corporation (January 2011-December 2012); Executive Vice President (January 2011-December 2012) and General Counsel of HarbourView Asset Management Corporation (since January 2011); Assistant Secretary (since January 2011) and Director (since January 2011) of OppenheimerFunds International Ltd. and OppenheimerFunds plc; Director of Oppenheimer Real Asset Management, Inc. (January 2011-December 2012) and General Counsel

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TRUSTEES AND OFFICERS Unaudited / Continued


Arthur S. Gabinet, Continued		(since January 2011); Executive Vice President (January 2011-December 2011) and General Counsel of Shareholder Financial Services, Inc. and Shareholder Services, Inc. (since January 2011); Executive Vice President (January 2011-December 2012) and General Counsel of OFI Private Investments Inc. (since January 2011); Vice President of OppenheimerFunds Legacy Program (January 2011-December 2011); Executive Vice President (January 2011-December 2012) and General Counsel of OFI Institutional Asset Management, Inc. (since January 2011); General Counsel, Asset Management of the Sub-Adviser (May 2010-December 2010); Principal, The Vanguard Group (November 2005-April 2010); District Administrator, U.S. Securities and Exchange Commission (January 2003-October 2005). An officer of 91 portfolios in the OppenheimerFunds complex.

Jennifer Sexton, Vice President and Chief Business Officer (since 2014) Year of Birth: 1969		Senior Vice President of OppenheimerFunds Distributor, Inc. (since June 2014); Vice President of OppenheimerFunds Distributor, Inc. (April 2006-June 2014); Vice President of the Sub-Adviser (January 1998-March 2006); Assistant Vice President of the Sub-Adviser (October 1991-December 1998). An officer of 91 portfolios in the OppenheimerFunds complex.

Mary Ann Picciotto, Chief Compliance Officer and Chief Anti-Money Laundering Officer (since 2014) Year of Birth: 1973		Senior Vice President and Chief Compliance Officer of the Manager (since March 2014); Chief Compliance Officer of the Sub-Adviser, OFI SteelPath, Inc., OFI Global Trust Company, OFI Global Institutional, Inc., Oppenheimer Real Asset Management, Inc., OFI Private Investments, Inc., Harborview Asset Management Corporation, Trinity Investment Management Corporation, and Shareholder Services, Inc. (since March 2014); Managing Director of Morgan Stanley Investment Management Inc. and certain of its various affiliated entities; Chief Compliance Officer of various Morgan Stanley Funds (May 2010-January 2014); Chief Compliance Officer of Morgan Stanley Investment Management Inc. (April 2007-January 2014). An officer of 91 portfolios in the OppenheimerFunds complex.

Brian W. Wixted, Treasurer and Principal Financial & Accounting Officer (since 1999) Year of Birth: 1959		Senior Vice President of the Manager (since January 2013); Treasurer of the Sub-Adviser, HarbourView Asset Management Corporation, Shareholder Financial Services, Inc., Shareholder Services, Inc., and Oppenheimer Real Asset Management, Inc. (March 1999-June 2008), OFI Private Investments, Inc. (March 2000-June 2008), OppenheimerFunds International Ltd. and OppenheimerFunds plc (since May 2000), OFI Institutional Asset Management, Inc. (November 2000-June 2008), and OppenheimerFunds Legacy Program (charitable trust program established by the Sub-Adviser) (June 2003-December 2011); Treasurer and Chief Financial Officer of OFI Trust Company (since May 2000); Assistant Treasurer of Oppenheimer Acquisition Corporation (March 1999-June 2008). An officer of 91 portfolios in the OppenheimerFunds complex.

The Fund’s Statement of Additional Information contains additional information about the Fund’s Trustees and Officers and is available without charge upon request, by calling 1.800.CALL OPP (225.5677).

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OPPENHEIMER MAIN STREET FUND


Manager		OFI Global Asset Management, Inc.

Sub-Adviser		OppenheimerFunds, Inc.

Distributor		OppenheimerFunds Distributor, Inc.

Transfer and Shareholder Servicing Agent		OFI Global Asset Management, Inc.

Sub-Transfer Agent		Shareholder Services, Inc. DBA OppenheimerFunds Services

Independent Registered Public Accounting Firm		KPMG LLP

Legal Counsel		K&LGates LLP

51 OPPENHEIMER MAIN STREET FUND

As an Oppenheimer fund shareholder, you are entitled to know how we protect your personal information and how we limit its disclosure.

Information Sources

We obtain nonpublic personal information about our shareholders from the following sources:

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Applications or other forms

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When you create a user ID and password for online account access

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When you enroll in eDocs Direct, our electronic document delivery service

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Your transactions with us, our affiliates or others

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A software program on our website, often referred to as a “cookie,” which indicates which parts of our site you’ve visited

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When you set up challenge questions to reset your password online

If you visit oppenheimerfunds.com and do not log on to the secure account information areas, we do not obtain any personal information about you. When you do log on to a secure area, we do obtain your user ID and password to identify you. We also use this information to provide you with products and services you have requested, to inform you about products and services that you may be interested in and assist you in other ways.

We do not collect personal information through our website unless you willingly provide it to us, either directly by email or in those areas of the website that request information. In order to update your personal information (including your mailing address, email address and phone number) you must first log on and visit your user profile.

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We do not disclose any non-public personal information (such as names on a customer list) about current or former customers to anyone, except as permitted by law.

Disclosure of Information

We send your financial advisor (as designated by you) copies of confirmations, account statements and other documents reporting activity in your fund accounts. We may also use details about you and your investments to help us, our financial service affiliates, or firms that jointly market their financial products and services with ours, to better serve your investment needs or suggest financial services or educational material that may be of interest to you. If this requires us to provide you with an opportunity to “opt in” or “opt out” of such information sharing with a firm not affiliated with us, you will receive notification on how to do so, before any such sharing takes place.

Right of Refusal

We will not disclose your personal information to unaffiliated third parties (except as permitted by law), unless we first offer you a reasonable opportunity to refuse or “opt out” of such disclosure.

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Internet Security and Encryption

In general, the email services provided by our website are encrypted and provide a secure and private means of communication with us. To protect your own privacy, confidential and/or personal information should only be communicated via email when you are advised that you are using a secure website.

As a security measure, we do not include personal or account information in non-secure emails, and we advise you not to send such information to us in non-secure emails. Instead, you may take advantage of the secure features of our website to encrypt your email correspondence. To do this, you will need to use a browser that supports Secure Sockets Layer (SSL) protocol.

We do not guarantee or warrant that any part of our website, including files available for download, are free of viruses or other harmful code. It is your responsibility to take appropriate precautions, such as use of an anti-virus software package, to protect your computer hardware and software.

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All transactions, including redemptions, exchanges and purchases, are secured by SSL and 128-bit encryption. SSL is used to establish a secure connection between your PC and OppenheimerFunds’ server. It transmits information in an encrypted and scrambled format.

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Encryption is achieved through an electronic scrambling technology that uses a “key” to code and then decode the data. Encryption acts like the cable converter box you may have on your television set. It scrambles data with a secret code so that no one can make sense of it while it is being transmitted. When the data reaches its destination, the same software unscrambles the data.

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You can exit the secure area by either closing your browser, or for added security, you can use the Log Out button before you close your browser.

Other Security Measures

We maintain physical, electronic and procedural safeguards to protect your personal account information. Our employees and agents have access to that information only so that they may offer you products or provide services, for example, when responding to your account questions.

How You Can Help

You can also do your part to keep your account information private and to prevent unauthorized transactions. If you obtain a user ID and password for your account, do not allow it to be used by anyone else. Also, take special precautions when accessing your account on a computer used by others.

Who We Are

This joint notice describes the privacy policies of the Oppenheimer funds, OppenheimerFunds, Inc., and each of its investment adviser subsidiaries, OppenheimerFunds Distributor, Inc. and OFI Global Trust Co. It applies to all Oppenheimer fund accounts you presently have, or may open in the future, using your Social Security number—whether or not you remain a shareholder of our funds. This notice was last updated November 2013. In the event it is updated or changed, we will post an updated notice on our website at oppenheimerfunds.com. If you have any questions about these privacy policies, write to us at P.O. Box 5270, Denver, CO 80217-5270, email us by clicking on the Contact Us section of our website at oppenheimerfunds.com or call us at 1.800.CALL OPP (225.5677).

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LOGO

Item 2. Code of Ethics.

The registrant has adopted a code of ethics that applies to the registrant’s principal executive officer, principal financial officer, principal accounting officer or controller or persons performing similar functions.

Item 3. Audit Committee Financial Expert.

The Board of Trustees of the registrant has determined that F. William Marshall, Jr., the Chairman of the Board’s Audit Committee, is the audit committee financial expert and that Mr. Marshall is “independent” for purposes of this Item 3.

Item 4. Principal Accountant Fees and Services.

(a)	Audit Fees

The principal accountant for the audit of the registrant’s annual financial statements billed $32,200 in fiscal 2014 and $31,500 in fiscal 2013.

(b)	Audit-Related Fees

The principal accountant for the audit of the registrant’s annual financial statements billed no such fees in fiscal 2014 and no such fees in fiscal 2013.

The principal accountant for the audit of the registrant’s annual financial statements billed $1,074,824 in fiscal 2014 and $566,580 in fiscal 2013 to the registrant’s investment adviser or any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant.

Such services include: Internal control reviews, GIPS attestation procedures, system conversion testing, and corporate restructuring.

(c)

Tax Fees

The principal accountant for the audit of the registrant’s annual financial statements billed no such fees in fiscal 2014 and no such fees in fiscal 2013.

The principal accountant for the audit of the registrant’s annual financial statements billed $336,709 in fiscal 2014 and $492,036 in fiscal 2013 to the registrant’s investment adviser or any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant.

Such services include: tax compliance, tax planning and tax advice. Tax compliance generally involves preparation of original and amended tax returns, claims for a refund and tax payment-planning services. Tax planning and tax advice includes assistance with tax audits and appeals, tax advice related to mergers and acquisitions and requests for rulings or technical advice from taxing authorities.

(d)	All Other Fees

The principal accountant for the audit of the registrant’s annual financial statements billed no such fees in fiscal 2014 and no such fees in fiscal 2013.

The principal accountant for the audit of the registrant’s annual financial statements billed no such fees in fiscal 2014 and no such fees in fiscal 2013 to the registrant’s investment adviser or any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant.

Such fees would include the cost to the principal accountant of attending audit committee meetings and consultations regarding the registrant’s retirement plan with respect to its Trustees.

(e)	(1) During its regularly scheduled periodic meetings, the registrant’s audit committee will pre-approve all audit, audit-related, tax and other services to be provided by the principal accountants of the registrant.

The audit committee has delegated pre-approval authority to its Chairman for any subsequent new engagements that arise between regularly scheduled meeting dates provided that any fees such pre-approved are presented to the audit committee at its next regularly scheduled meeting.

Under applicable laws, pre-approval of non-audit services may be waived provided that: 1) the aggregate amount of all such services provided constitutes no more than five percent of the total amount of fees paid by the registrant to its principal accountant during the fiscal year in which services are provided 2) such services were not recognized by the registrant at the time of engagement as non-audit services and 3) such services are promptly brought to the attention of the audit committee of the registrant and approved prior to the completion of the audit.

(2) 0%

(f)	Not applicable as less than 50%.

(g)

The principal accountant for the audit of the registrant’s annual financial statements billed $1,411,533 in fiscal 2014 and $1,058,616 in fiscal 2013 to the registrant and the registrant’s investment adviser or any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant related to non-audit fees. Those billings did not include any prohibited non-audit services as defined by the Securities Exchange Act of 1934.

(h)

The registrant’s audit committee of the board of Trustees has considered whether the provision of non-audit services that were rendered to the registrant’s investment adviser, and any entity controlling, controlled by, or under common control with the investment adviser that provides ongoing services to the registrant that were not pre-approved pursuant to paragraph (c)(7)(ii) of Rule 2-01 of Regulation S-X is compatible with maintaining the principal accountant’s independence. No such services were rendered.

Item 5. Audit Committee of Listed Registrants

Not applicable.

Item 6. Schedule of Investments.

a) Not applicable. The complete schedule of investments is included in Item 1 of this Form N-CSR.

b) Not applicable.

Item 7. Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies.

Not applicable.

Item 8. Portfolio Managers of Closed-End Management Investment Companies.

Not applicable.

Item 9. Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers.

Not applicable.

Item 10. Submission of Matters to a Vote of Security Holders.

The Fund’s Governance Committee Provisions with Respect to Nominations of Directors/Trustees to the Respective Boards

None

Item 11. Controls and Procedures.

Based on their evaluation of the registrant’s disclosure controls and procedures (as defined in rule 30a-3(c) under the Investment Company Act of 1940 (17 CFR 270.30a-3(c)) as of 8/29/2014, the registrant’s principal executive officer and principal financial officer found the registrant’s disclosure controls and procedures to provide reasonable assurances that information required to be disclosed by the registrant in the reports that it files under the Securities Exchange Act of 1934 (a) is accumulated and communicated to registrant’s management, including its principal executive officer and principal financial officer, to allow timely decisions regarding required disclosure, and (b) is recorded, processed, summarized and reported, within the time periods specified in the rules and forms adopted by the U.S. Securities and Exchange Commission.

There have been no changes in the registrant’s internal controls over financial reporting that occurred during the registrant’s second fiscal quarter of the period covered by this report that have materially affected, or are reasonably likely to materially affect, the registrant’s internal control over financial reporting.

Item 12. Exhibits.

(a)	(1) Exhibit attached hereto.

(2) Exhibits attached hereto.

(3) Not applicable.

(b)	Exhibit attached hereto.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Oppenheimer Main Street Funds


By:		/s/ Arthur P. Steinmetz
		Arthur P. Steinmetz
		Principal Executive Officer

Date:		10/9/2014

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.


By:		/s/ Arthur P. Steinmetz
		Arthur P. Steinmetz
		Principal Executive Officer

Date:		10/9/2014


By:		/s/ Brian W. Wixted
		Brian W. Wixted
		Principal Financial Officer

Date:		10/9/2014

Year Ended August 29, 2014

Year Ended August 30, 2013

Year Ended August 31, 2012

Year Ended August 31, 2011

Year Ended August 31, 2010