Dreyfus Basic U S Government Money Market Fund NCSRS Certified semi-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			811-6606

	Dreyfus BASIC U.S. Government Money Market Fund
	(Exact name of Registrant as specified in charter)

	c/o The Dreyfus Corporation 200 Park Avenue New York, New York 10166
	(Address of principal executive offices) (Zip code)

	Michael A. Rosenberg, Esq. 200 Park Avenue New York, New York 10166
	(Name and address of agent for service)

Registrant's telephone number, including area code:				(212) 922-6000

Date of fiscal year end:		2/28
Date of reporting period:		8/31/11

FORM N-CSR

Item 1. Reports to Stockholders.

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The views expressed in this report reflect those of the portfolio manager only through the end of the period covered and do not necessarily represent the views of Dreyfus or any other person in the Dreyfus organization. Any such views are subject to change at any time based upon market or other conditions and Dreyfus disclaims any responsibility to update such views.These views may not be relied on as investment advice and, because investment decisions for a Dreyfus fund are based on numerous factors, may not be relied on as an indication of trading intent on behalf of any Dreyfus fund.

Not FDIC-Insured • Not Bank-Guaranteed • May Lose Value

	Contents
	THE FUND
2	A Letter from the Chairman and CEO
3	Discussion of Fund Performance
6	Understanding Your Fund’s Expenses
6	Comparing Your Fund’s Expenses With Those of Other Funds
7	Statement of Investments
9	Statement of Assets and Liabilities
10	Statement of Operations
11	Statement of Changes in Net Assets
12	Financial Highlights
13	Notes to Financial Statements
20	Information About the Renewal of the Fund’s Management Agreement
	FOR MORE INFORMATION
	Back Cover

Dreyfus BASIC
U.S. Government
Money Market Fund

The Fund

A LETTER FROM THE CHAIRMAN AND CEO

Dear Shareholder:

We are pleased to present this semiannual report for Dreyfus BASIC U.S. Government Money Market Fund, covering the six-month period from March 1, 2011, through August 31, 2011. For information about how the fund performed during the reporting period, as well as general market perspectives, we provide a Discussion of Fund Performance on the pages that follow.

Although investors were encouraged by expectations of a more robust economic recovery through the first quarter of 2011, the reporting period ended amid sharply deteriorating investor sentiment due to disappointing economic data, an escalating sovereign debt crisis in Europe and a contentious debate regarding taxes, spending and borrowing in the United States. In the final month of the reporting period, a major credit rating agency downgraded U.S. long-term debt, marking the first time in history that U.S.Treasury securities were not assigned the highest possible credit rating. However, the U.S. short-term debt — in which money market funds invest — maintained its highest credit rating designation among all three major rating agencies.

The economic outlook currently is clouded by heightened market volatility and political infighting, but we believe that a sustained, moderate global expansion is more likely than a double-dip recession. Inflationary pressures appear to be waning in most countries, including the United States, as energy prices have retreated from their highs.The Federal Reserve Board has signaled its intention to maintain an aggressively accommodative monetary policy, which may help offset the financial stresses caused by recent fiscal policy choices in the United States and Europe. However, the Fed’s policy stance also seems likely to keep money market yields at current levels. To assess how these and other developments may affect your investments, we encourage you, as always, to speak with your financial advisor.

Thank you for your continued confidence and support.

Jonathan R. Baum
Chairman and Chief Executive Officer
The Dreyfus Corporation
September 15, 2011

DISCUSSION OF FUND PERFORMANCE

For the period of March 1, 2011, through August 31, 2011, as provided by Bernard W. Kiernan, Jr., Portfolio Manager

Fund and Market Performance Overview

For the six-month period ended August 31, 2011, Dreyfus BASIC U.S. Government Money Market Fund produced an annualized yield of 0.00%. Taking into account the effects of compounding, the fund produced an annualized effective yield of 0.00%.¹

Yields of money market instruments hovered near historically low levels throughout the reporting period as short-term interest rates remained unchanged in a faltering U.S. economy.

The Fund’s Investment Approach

The fund seeks as high a level of current income as is consistent with the preservation of capital and the maintenance of liquidity.To pursue this goal, the fund invests exclusively in securities issued or guaranteed as to principal and interest by the U.S. government or its agencies or instrumentalities, and in repurchase agreements (including tri-party repurchase agreements).The securities in which the fund invests include those backed by the full faith and credit of the U.S. government and those that are neither insured nor guaranteed by the U.S. government.

When managing the fund, we closely monitor the outlook for economic growth and inflation, follow overseas developments and consider the posture of the Federal Reserve Board (the “Fed”) in our decisions as to how to structure the fund. Based upon our economic outlook, we actively manage the fund’s average maturity in looking for opportunities that may present themselves in light of possible changes in interest rates.

Mixed Economic Data Sparked Shifts in Market Sentiment

The reporting period began in the midst of an apparent economic recovery. The unemployment rate had eased to 8.9% by the end of February 2011, and the Fed was engaged in a quantitative easing pro-


The Fund	3

DISCUSSION OF FUND PERFORMANCE (continued)

gram involving the purchase of $600 million of U.S.Treasury securities. Meanwhile, food and fuel prices climbed, in part due to political turmoil in the Middle East, signaling a potential increase in inflationary pressures. Nonetheless, as it has since December 2008, the Fed maintained an aggressively accommodative monetary policy, keeping short-term interest rates within a historically low range between 0% and 0.25%.

The global economy took another hit in March, when Japan suffered a devastating earthquake, tsunami and nuclear disaster, disrupting the global industrial supply chain. Yet, activity expanded across several sectors of the U.S. economy in March, the private sector added 233,000 jobs and the unemployment rate dropped to 8.8%, its lowest reading in two years. However, it was later announced that the U.S. economy grew at a surprisingly anemic 0.4% annualized rate during the first quarter of 2011. Slowdowns in consumer and government spending appeared to be the main factors behind the deceleration of economic growth.

Economic headwinds intensified in April when Greece appeared headed toward defaulting on its sovereign debt. In addition, a contentious debate about government spending and borrowing dominated headlines in the United States as the federal government approached the upper limits of its debt authorization. However, some parts of the U.S. economy continued to fare well, including domestic manufacturing.

May produced more mixed economic data.While industrial production picked up, employment data continued to disappoint.The housing market continued to deteriorate, posting declines in existing home sales and housing starts.The Fed ended its quantitative easing program in June, and investors were relieved when the program’s termination had relatively little immediate impact on the financial markets. Meanwhile, energy prices moderated, and manufacturing activity continued to increase. These positive developments were largely offset by declining consumer confidence, weakness in U.S. housing markets and sluggish job creation.

July saw heightened turmoil in the financial markets as Greece moved closer to default, other peripheral European nations struggled with heavy debt loads and the U.S. Congress continued to engage in a

rancorous debate about the federal budget deficit. Some of these worries came to a head in early August, when Congress passed legislation cutting government spending and raising the U.S. debt ceiling, and Standard & Poor’s downgraded its credit rating on long-term U.S. debt securities. The rating on short-term government debt, including securities purchased by many money market funds, was unchanged. Later in the month, hurricanes, drought and wildfires inflicted additional damage on an already battered economy.

Outlook Clouded by Recent Events

Yields of money market instruments remained near zero percent throughout the reporting period, and with narrow yield differences along the market’s maturity spectrum, it continued to make little sense to incur the additional risks that longer-dated securities typically entail.Therefore, we maintained the fund’s weighted average maturity in a range that was roughly in line with industry averages.

The reporting period ended with a cloudy economic outlook for the remainder of the year and beyond. However, the Fed recently signaled that it is prepared to keep short-term interest rates near historical lows “at least through mid-2013.” Therefore, we intend to maintain the fund’s focus on liquidity.

September 15, 2011


	An investment in the fund is not insured or guaranteed by the FDIC or any other government
	agency.Although the fund seeks to preserve the value of your investment at $1.00 per share, it is
	possible to lose money by investing in the fund.
1	Annualized effective yield is based upon dividends declared daily and reinvested monthly. Past
	performance is no guarantee of future results.Yields fluctuate.Yield provided reflects the absorption
	of certain fund expenses by The Dreyfus Corporation pursuant to an agreement in which
	shareholders will be given at least 90 days’ notice prior to or at least not until July 1, 2012, the
	time such absorption may be terminated. Had these expenses not been absorbed, fund yields
	would have been lower, and in some cases, 7-day yields during the reporting period would have
	been negative absent the expense absorption.


The Fund	5

UNDERSTANDING YOUR FUND’S EXPENSES (Unaudited)

As a mutual fund investor, you pay ongoing expenses, such as management fees and other expenses. Using the information below, you can estimate how these expenses affect your investment and compare them with the expenses of other funds.You also may pay one-time transaction expenses, including sales charges (loads) and redemption fees, which are not shown in this section and would have resulted in higher total expenses. For more information, see your fund’s prospectus or talk to your financial adviser.

Review your fund’s expenses

The table below shows the expenses you would have paid on a $1,000 investment in Dreyfus BASIC U.S. Government Money Market Fund from March 1, 2011 to August 31, 2011. It also shows how much a $1,000 investment would be worth at the close of the period, assuming actual returns and expenses.


Expenses and Value of a $1,000 Investment
assuming actual returns for the six months ended August 31, 2011

Expenses paid per $1,000^†	$ .70
Ending value (after expenses)	$1,000.00

COMPARING YOUR FUND’S EXPENSES

WITH THOSE OF OTHER FUNDS (Unaudited)

Using the SEC’s method to compare expenses

The Securities and Exchange Commission (SEC) has established guidelines to help investors assess fund expenses. Per these guidelines, the table below shows your fund’s expenses based on a $1,000 investment, assuming a hypothetical 5% annualized return. You can use this information to compare the ongoing expenses (but not transaction expenses or total cost) of investing in the fund with those of other funds.All mutual fund shareholder reports will provide this information to help you make this comparison. Please note that you cannot use this information to estimate your actual ending account balance and expenses paid during the period.


Expenses and Value of a $1,000 Investment
assuming a hypothetical 5% annualized return for the six months ended August 31, 2011

Expenses paid per $1,000^†	$ .71
Ending value (after expenses)	$1,024.43

† Expenses are equal to the fund’s annualized expense ratio of .14%, multiplied by the average account value over the period, multiplied by 184/366 (to reflect the one-half year period).

STATEMENT OF INVESTMENTS

August 31, 2011 (Unaudited)


	Annualized
	Yield on
	Date of	Principal
U.S. Government Agencies—30.8%	Purchase (%)	Amount ($)	Value ($)
Federal Home Loan Mortgage Corp.:
10/24/11	0.11	10,000,000 ^a	9,998,381
11/28/11	0.13	15,000,000 ^a	14,995,233
Federal National Mortgage Association:
10/26/11	0.10	15,000,000 ^a	14,997,823
12/14/11	0.14	5,000,000 ^a	4,997,978
2/1/13	0.40	10,000,000 ^a,b10,000,000
Total U.S. Government Agencies
(cost $54,989,415)			54,989,415


U.S. Treasury Bills—25.2%
9/22/11
(cost $44,999,905)	0.00	45,000,000	44,999,905


U.S. Treasury Notes—5.6%
11/15/11	0.29	5,000,000	5,014,876
2/29/12	0.28	5,000,000	5,014,572
Total U.S. Treasury Notes
(cost $10,029,448)			10,029,448


Repurchase Agreements—38.7%
Barclays Capital, Inc.
dated 8/31/11, due 9/1/11 in the amount
of $14,000,012 (fully collateralized by
$12,033,200 U.S. Treasury Bonds, 4.50%,
due 8/15/39, value $14,280,118)	0.03	14,000,000	14,000,000
Deutsche Bank Securities Inc.
dated 8/31/11, due 9/1/11 in the amount
of $30,000,042 (fully collateralized by
$30,438,800 U.S. Treasury Notes, 0.50%,
due 8/15/14, value $30,600,046)	0.05	30,000,000	30,000,000


The Fund	7

STATEMENT OF INVESTMENTS (Unaudited) (continued)


	Annualized
	Yield on
	Date of	Principal
Repurchase Agreements (continued)	Purchase (%)	Amount ($)	Value ($)
HSBC USA Inc.
dated 8/31/11, due 9/1/11 in the amount
of $25,000,028 (fully collateralized by
$25,504,000 U.S. Treasury Bills,
due 10/6/11-2/16/12, value $25,503,343)	0.04	25,000,000	25,000,000
Total Repurchase Agreements
(cost $69,000,000)			69,000,000

Total Investments (cost $179,018,768)		100.3%	179,018,768

Liabilities, Less Cash and Receivables		(.3%)	(545,016)

Net Assets		100.0%	178,473,752

a The Federal Housing Finance Agency (“FHFA”) placed Federal Home Loan Mortgage Corporation and Federal

National Mortgage Association into conservatorship with FHFA as the conservator.As such, the FHFA oversees the

continuing affairs of these companies.

b Variable rate security—interest rate subject to periodic change.


Portfolio Summary (Unaudited)^†

	Value (%)		Value (%)

Repurchase Agreements	38.7	Federal Home Loan Mortgage Corp.	14.0
U.S. Treasury Bills	25.2	U.S. Treasury Notes	5.6
Federal National
Mortgage Association	16.8		100.3

† Based on net assets.
See notes to financial statements.

STATEMENT OF ASSETS AND LIABILITIES

August 31, 2011 (Unaudited)


	Cost	Value
Assets ($):
Investments in securities—See Statement of
Investments (including Repurchase Agreements
of $69,000,000)—Note 1(b)	179,018,768	179,018,768
Cash		219,653
Interest receivable		29,465
Prepaid expenses		12,051
Due from The Dreyfus Corporation and affiliates—Note 2(b)		3,768
		179,283,705
Liabilities ($):
Payable for shares of Beneficial Interest redeemed		756,926
Accrued expenses		53,027
		809,953
Net Assets ($)		178,473,752
Composition of Net Assets ($):
Paid-in capital		178,480,834
Accumulated net realized gain (loss) on investments		(7,082)
Net Assets ($)		178,473,752
Shares Outstanding
(unlimited number of $.001 par value shares of Beneficial interest authorized)		178,491,496
Net Asset Value, offering and redemption price per share ($)		1.00

See notes to financial statements.


The Fund	9

STATEMENT OF OPERATIONS

Six Months Ended August 31, 2011 (Unaudited)


Investment Income ($):
Interest Income	129,694
Expenses:
Management fee—Note 2(a)	479,851
Shareholder servicing costs—Note 2(b)	104,943
Auditing fees	19,569
Legal fees	17,090
Prospectus and shareholders’ reports	15,523
Registration fees	14,348
Custodian fees—Note 2(b)	7,273
Trustees’ fees and expenses—Note 2(c)	7,265
Miscellaneous	9,049
Total Expenses	674,911
Less—reduction in management fee due to undertaking—Note 2(a)	(243,041)
Less—reduction in expenses due to undertaking—Note 2(a)	(301,843)
Less—reduction in fees due to earnings credits—Note 1(b)	(334)
Net Expenses	129,693
Investment Income—Net	1
Net Realized Gain (Loss) on Investments—Note 1(b) ($)	4,315
Net Increase in Net Assets Resulting from Operations	4,316

See notes to financial statements.

STATEMENT OF CHANGES IN NET ASSETS


	Six Months Ended
	August 31, 2011	Year Ended
	(Unaudited)	February 28, 2011
Operations ($):
Investment income—net	1	14
Net realized gain (loss) on investments	4,315	5,497
Net Increase (Decrease) in Net Assets
Resulting from Operations	4,316	5,511
Dividends to Shareholders from ($):
Investment income—net	(1)	(10,676)
Beneficial Interest Transactions ($1.00 per share):
Net proceeds from shares sold	20,695,231	69,524,767
Dividends reinvested	5	9,954
Cost of shares redeemed	(39,856,149)	(118,240,195)
Increase (Decrease) in Net Assets from
Beneficial Interest Transactions	(19,160,913)	(48,705,474)
Total Increase (Decrease) in Net Assets	(19,156,598)	(48,710,639)
Net Assets ($):
Beginning of Period	197,630,350	246,340,989
End of Period	178,473,752	197,630,350

See notes to financial statements.


The Fund	11

FINANCIAL HIGHLIGHTS

The following table describes the performance for the fiscal periods indicated. Total return shows how much your investment in the fund would have increased (or decreased) during each period, assuming you had reinvested all dividends and distributions.These figures have been derived from the fund’s financial statements.


Six Months Ended
August 31, 2011			Year Ended February 28/29,
	(Unaudited)	2011	2010	2009	2008	2007
Per Share Data ($):
Net asset value,
beginning of period	1.00	1.00	1.00	1.00	1.00	1.00
Investment Operations:
Investment income—net	.000^a	.000^a	.000^a	.016	.045	.047
Distributions:
Dividends from
investment income—net	(.000)^a	(.000)^a(.000)^a		(.016)	(.045)	(.047)
Net asset value, end of period	1.00	1.00	1.00	1.00	1.00	1.00
Total Return (%)	.00^b,c	.01	.03	1.64	4.56	4.79
Ratios/Supplemental Data (%):
Ratio of total expenses
to average net assets	.70^b	.69	.67	.65	.63	.63
Ratio of net expenses
to average net assets	.14^b	.24	.38	.46	.45	.45
Ratio of net investment income
to average net assets	.00^b,c	.00^c	.03	1.67	4.46	4.67
Net Assets, end of period
($ x 1,000)	178,474 197,630		246,341	345,292	399,929	391,079


a	Amount represents less than $.001 per share.
b	Annualized.
c	Amount represents less than .01%.
See notes to financial statements.

NOTES TO FINANCIAL STATEMENTS (Unaudited)

NOTE 1—Significant Accounting Policies:

Dreyfus BASIC U.S. Government Money Market Fund (the “fund”) is registered under the Investment Company Act of 1940, as amended (the “Act”), as a diversified open-end management investment company. The fund’s investment objective is to seek as high a level of current income as is consistent with the preservation of capital and the maintenance of liquidity. The Dreyfus Corporation (the “Manager” or “Dreyfus”), a wholly-owned subsidiary of The Bank of New York Mellon Corporation (“BNY Mellon”), serves as the fund’s investment adviser. MBSC Securities Corporation (the “Distributor”), a wholly-owned subsidiary of the Manager, is the distributor of the fund’s shares, which are sold to the public without a sales charge.

It is the fund’s policy to maintain a continuous net asset value per share of $1.00; the fund has adopted certain investment, portfolio valuation and dividend and distribution policies to enable it to do so.There is no assurance, however, that the fund will be able to maintain a stable net asset value per share of $1.00.

The Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) is the exclusive reference of authoritative U.S. generally accepted accounting principles (“GAAP”) recognized by the FASB to be applied by nongovernmental entities. Rules and interpretive releases of the Securities and Exchange Commission (“SEC”) under authority of federal laws are also sources of authoritative GAAP for SEC registrants. The fund’s financial statements are prepared in accordance with GAAP, which may require the use of management estimates and assumptions.Actual results could differ from those estimates.

The fund enters into contracts that contain a variety of indemnifications. The fund’s maximum exposure under these arrangements is unknown.The fund does not anticipate recognizing any loss related to these arrangements.


The Fund	13

NOTES TO FINANCIAL STATEMENTS (Unaudited) (continued)

(a) Portfolio valuation: Investments in securities are valued at amortized cost in accordance with Rule 2a-7 of the Act, which has been determined by the Board of Trustees to represent the fair value of the fund’s investments.

The fair value of a financial instrument is the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (i.e. the exit price). GAAP establishes a fair value hierarchy that prioritizes the inputs of valuation techniques used to measure fair value.This hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements).

Additionally, GAAP provides guidance on determining whether the volume and activity in a market has decreased significantly and whether such a decrease in activity results in transactions that are not orderly. GAAP requires enhanced disclosures around valuation inputs and techniques used during annual and interim periods.

Various inputs are used in determining the value of the fund’s investments relating to fair value measurements.These inputs are summarized in the three broad levels listed below:

Level 1—unadjusted quoted prices in active markets for identical investments.

Level 2—other significant observable inputs (including quoted prices for similar investments, interest rates, prepayment speeds, credit risk, etc.).

Level 3—significant unobservable inputs (including the fund’s own assumptions in determining the fair value of investments).

The inputs or methodology used for valuing securities are not necessarily an indication of the risk associated with investing in those securities. For example, money market securities are valued using amortized cost, in accordance with rules under the Act. Generally, amortized cost approximates the current fair value of a security, but since the value is

not obtained from a quoted price in an active market, such securities are reflected as Level 2.

The following is a summary of the inputs used as of August 31, 2011 in valuing the fund’s investments:


	Short-Term
Valuation Inputs	Investments ($)^†
Level 1—Unadjusted Quoted Prices	—
Level 2—Other Significant Observable Inputs	179,018,768
Level 3—Significant Unobservable Inputs	—
Total	179,018,768
† See Statement of Investments for additional detailed categorizations.

(b) Securities transactions and investment income: Securities transactions are recorded on a trade date basis. Realized gains and losses from securities transactions are recorded on the identified cost basis. Interest income, adjusted for accretion of discount and amortization of premium on investments, is earned from settlement date and is recognized on the accrual basis. Cost of investments represents amortized cost.

The fund may enter into repurchase agreements with financial institutions, deemed to be creditworthy by the Manager, subject to the seller’s agreement to repurchase and the fund’s agreement to resell such securities at a mutually agreed upon price. Securities purchased subject to repurchase agreements are deposited with the fund’s custodian and, pursuant to the terms of the repurchase agreement, must have an aggregate market value greater than or equal to the terms of the repurchase price plus accrued interest at all times. If the value of the underlying securities falls below the value of the repurchase price plus accrued interest, the fund will require the seller to deposit additional collateral by the next business day. If the request for additional collateral is not met, or the seller defaults on its repurchase obligation, the fund maintains its right to sell the underlying securities at market value and may claim any resulting loss against the seller.


The Fund	15

NOTES TO FINANCIAL STATEMENTS (Unaudited) (continued)

(c) Dividends to shareholders: It is the policy of the fund to declare dividends daily from investment income-net. Such dividends are paid monthly. Dividends from net realized capital gains, if any, are normally declared and paid annually, but the fund may make distributions on a more frequent basis to comply with the distribution requirements of the Internal Revenue Code of 1986, as amended (the “Code”).To the extent that net realized capital gains can be offset by capital loss carryovers, it is the policy of the fund not to distribute such gains.

(d) Federal income taxes: It is the policy of the fund to continue to qualify as a regulated investment company, if such qualification is in the best interests of its shareholders, by complying with the applicable provisions of the Code, and to make distributions of taxable income sufficient to relieve it from substantially all federal income and excise taxes.

As of and during the period ended August 31, 2011, the fund did not have any liabilities for any uncertain tax positions.The fund recognizes interest and penalties, if any, related to uncertain tax positions as income tax expense in the Statement of Operations. During the period, the fund did not incur any interest or penalties.

Each of the tax years in the three-year period ended February 28, 2011 remains subject to examination by the Internal Revenue Service and state taxing authorities.

The fund has an unused capital loss carryover of $11,397 available for federal income tax purposes to be applied against future net securities profits, if any, realized subsequent to February 28, 2011. If not applied, $9,327 of the carryover expires in fiscal 2013 and $2,070 expires in fiscal 2014.

The tax character of distributions paid to shareholders during the fiscal year ended February 28, 2011 was all ordinary income. The tax character of current year distributions will be determined at the end of the current fiscal year.

At August 31, 2011, the cost of investments for federal income tax purposes was substantially the same as the cost for financial reporting purposes (see the Statement of Investments).

NOTE 2—Management Fee and Other Transactions With Affiliates:

(a) Pursuant to a management agreement (“Agreement”) with the Manager, the management fee is computed at the annual rate of .50% of the value of the fund’s average daily net assets and is payable monthly. The Manager has undertaken, if the fund’s aggregate expenses, exclusive of taxes, brokerage fees, interest on borrowings and extraordinary expenses, exceed an annual rate of .45% of the value of the fund’s average daily net assets, the fund may deduct from the payment to be made to the Manager under the Agreement, or the Manager will bear, such excess expense. The Manager may terminate this undertaking agreement upon at least 90 days’ prior notice to shareholders but has committed not to do so until at least July 1, 2012. The reduction in management fee, pursuant to the undertaking, amounted to $243,041 during the period ended August 31, 2011.

The Manager has undertaken to waive receipt of the management fee and/or reimburse operating expenses in order to facilitate a daily yield at or above a certain level. Such level may change from time to time, is voluntary and not contractual, and may be terminated at any time. The reduction in expenses, pursuant to the undertaking, amounted to $301,843 during the period ended August 31, 2011.

(b) Under the Shareholder Services Plan, the fund reimburses the Distributor an amount not to exceed an annual rate of .25% of the value of the fund’s average daily net assets for certain allocated expenses of providing personal services and/or maintaining shareholder accounts.The services provided may include personal services relating to shareholder accounts, such as answering shareholder inquiries regarding the fund and providing reports and other information, and services related to the maintenance of shareholder accounts. During the period ended August 31, 2011, the fund was charged $74,972 pursuant to the Shareholder Services Plan.


The Fund	17

NOTES TO FINANCIAL STATEMENTS (Unaudited) (continued)

The fund compensates Dreyfus Transfer, Inc., a wholly-owned subsidiary of the Manager, under a transfer agency agreement for providing personnel and facilities to perform transfer agency services for the fund. During the period ended August 31, 2011, the fund was charged $21,438 pursuant to the transfer agency agreement, which is included in Shareholder servicing costs in the Statement of Operations.

The fund has arrangements with the custodian and cash management bank whereby the fund may receive earnings credits when positive cash balances are maintained, which are used to offset custody and cash management fees. For financial reporting purposes, the fund includes net earnings credits as an expense offset in the Statement of Operations.

The fund compensates The Bank of NewYork Mellon, a subsidiary of BNY Mellon and an affiliate of Dreyfus, under a cash management agreement for performing cash management services related to fund subscriptions and redemptions. During the period ended August 31, 2011, the fund was charged $2,121 pursuant to the cash management agreement, which is included in Shareholder servicing costs in the Statement of Operations. These fees were partially offset by earnings credits of $48.

The fund also compensates The Bank of New York Mellon under a custody agreement for providing custodial services for the fund. During the period ended August 31, 2011, the fund was charged $7,273 pursuant to the custody agreement. These fees were partially offset by earnings credits of $286.

During the period ended August 31, 2011, the fund was charged $2,981 for services performed by the Chief Compliance Officer.

The components of“Due fromThe Dreyfus Corporation and affiliates” in the Statement of Assets and Liabilities consist of: management fees $76,245, custodian fees $8,092, chief compliance officer fees $3,253 and transfer agency per account fees $6,961, which are offset against an expense reimbursement currently in effect in the amount of $98,319.

(c) Each Board member also serves as a Board member of other funds within the Dreyfus complex. Annual retainer fees and attendance fees are allocated to each fund based on net assets.


The Fund	19

INFORMATION ABOUT THE RENEWAL OF THE

FUND’S MANAGEMENT AGREEMENT (Unaudited)

At a meeting of the fund’s Board of Trustees held on July 26, 2011, the Board considered the renewal of the fund’s Management Agreement pursuant to which Dreyfus provides the fund with investment advisory and administrative services (the “Agreement”). The Board members, none of whom are “interested persons” (as defined in the Investment Company Act of 1940, as amended) of the fund, were assisted in their review by independent legal counsel and met with counsel in executive session separate from representatives of Dreyfus. In considering the renewal of the Agreement, the Board considered all factors that it believed to be relevant, including those discussed below.The Board did not identify any one factor as dispositive, and each Board member may have attributed different weights to the factors considered.

Analysis of Nature, Extent, and Quality of Services Provided to the Fund.The Board members considered information previously provided to them in presentations from representatives of Dreyfus regarding the nature, extent, and quality of the services provided to funds in the Dreyfus fund complex, and representatives of Dreyfus confirmed that there had been no material changes in this information. Dreyfus provided the number of open accounts in the fund, the fund’s asset size and the allocation of fund assets among distribution channels. Dreyfus also had previously provided information regarding the diverse intermediary relationships and distribution channels of funds in the Dreyfus fund complex and Dreyfus’ corresponding need for broad, deep, and diverse resources to be able to provide ongoing shareholder services to each distribution channel, including the distribution channel(s) for the fund.

The Board members also considered research support available to, and portfolio management capabilities of, the fund’s portfolio management personnel and that Dreyfus also provides oversight of day-to-day fund operations, including fund accounting and administration and assistance in meeting legal and regulatory requirements.The Board members also considered Dreyfus’ extensive administrative, accounting, and compliance infrastructures.

Comparative Analysis of the Fund’s Performance and Management Fee and Expense Ratio. The Board members reviewed reports prepared by Lipper, Inc. (“Lipper”), an independent provider of investment company data, which included information comparing (1) the fund’s performance with the performance of a group of comparable funds (the “Performance Group”) and with a broader group of funds (the “Performance Universe”), all for various periods ended June 30, 2011, and (2) the fund’s actual and contractual management fees and total expenses with those of a group of comparable funds (the “Expense Group”) and with a broader group of funds (the “Expense Universe”), the information for which was derived in part from fund financial statements available to Lipper as of June 30, 2011. Dreyfus previously had furnished the Board with a description of the methodology Lipper used to select the Performance Group and Performance Universe and the Expense Group and Expense Universe.

Dreyfus representatives stated that the usefulness of performance comparisons may be affected by a number of factors, including different investment limitations that may be applicable to the fund and comparison funds. The Board members discussed the results of the comparisons and noted that the fund’s total return performance was above the Performance Group and Performance Universe medians for the various periods, except for the one- and two- year periods when the fund’s performance was below the Performance Group and Performance Universe medians.

The Board members also reviewed the range of actual and contractual management fees and total expenses of the Expense Group and Expense Universe funds and discussed the results of the comparisons.They noted that the fund’s contractual management fee was at the Expense Group median, that the fund’s actual management fee was below the Expense Group and Expense Universe medians and that the fund’s total expenses were above the Expense Group and Expense Universe medians.


The Fund	21

INFORMATION ABOUT THE RENEWAL OF THE FUND’S

MANAGEMENT AGREEMENT (Unaudited) (continued)

A representative of Dreyfus noted that Dreyfus has contractually agreed, until at least July 1, 2012, to waive receipt of its fees and/or assume the expenses of the fund, so that annual direct fund operating expenses (excluding taxes, interest, brokerage commissions, acquired fund fees and extraordinary expenses) do not exceed .45% of the fund’s average daily net assets.

Representatives of Dreyfus reviewed with the Board members the management or investment advisory fees paid by funds advised or administered by Dreyfus that are in the same Lipper category as the fund (the “Similar Clients”), and explained the nature of the Similar Clients.They discussed differences in fees paid and the relationship of the fees paid in light of any differences in the services provided and other relevant factors.The Board members considered the relevance of the fee information provided for the Similar Clients to evaluate the appropriateness and reasonableness of the fund’s management fee.

Analysis of Profitability and Economies of Scale. Dreyfus’ representatives reviewed the expenses allocated and profit received by Dreyfus and the resulting profitability percentage for managing the fund, and the method used to determine the expenses and profit. The Board concluded that the profitability results were not unreasonable, given the services rendered and service levels provided by Dreyfus. The Board also noted the expense limitation arrangement and its effect on Dreyfus’ profitability. The Board previously had been provided with information prepared by an independent consulting firm regarding Dreyfus’ approach to allocating costs to, and determining the profitability of, individual funds and the entire Dreyfus fund complex.The consulting firm also had analyzed where any economies of scale might emerge in connection with the management of a fund.

The Board’s counsel stated that the Board members should consider the profitability analysis (1) as part of their evaluation of whether the fees under the Agreement bear a reasonable relationship to the mix of services provided by Dreyfus, including the nature, extent and quality of such services, and (2) in light of the relevant circumstances for the

fund and the extent to which economies of scale would be realized if the fund grows and whether fee levels reflect these economies of scale for the benefit of fund shareholders. Dreyfus representatives noted that a discussion of economies of scale is predicated on a fund having achieved a substantial size with increasing assets and that, if a fund’s assets had been stable or decreasing, the possibility that Dreyfus may have realized any economies of scale would be less. They also noted that, as a result of shared and allocated costs among funds in the Dreyfus funds complex, the extent of economies of scale could depend substantially on the level of assets in the complex as a whole, so that increases and decreases in complex-wide assets can affect potential economies of scale in a manner that is disproportionate to, or even in the opposite direction from, changes in the fund’s asset level. The Board members also considered potential benefits to Dreyfus from acting as investment adviser and noted that there were no soft dollar arrangements in effect for trading the fund’s investments.

At the conclusion of these discussions, the Board agreed that it had been furnished with sufficient information to make an informed business decision with respect to the renewal of the Agreement. Based on the discussions and considerations as described above, the Board concluded and determined as follows.

The Board concluded that the nature, extent and quality of the services provided by Dreyfus are adequate and appropriate.
The Board generally was satisfied with the fund’s relative performance.
The Board concluded that the fee paid to Dreyfus was reasonable in light of the considerations described above.
The Board determined that the economies of scale which may accrue to Dreyfus and its affiliates in connection with the management of the fund had been adequately considered by Dreyfus in connection with the fee rate charged to the fund pursuant to the Agreement and that, to the extent in the future it were determined that material economies of scale had not been shared with the fund, the Board would seek to have those economies of scale shared with the fund.


The Fund	23

INFORMATION ABOUT THE RENEWAL OF THE FUND’S

MANAGEMENT AGREEMENT (Unaudited) (continued)

The Board members considered these conclusions and determinations, along with information received on a routine and regular basis throughout the year. In addition, it should be noted that the Board’s consideration of the contractual fee arrangements for this fund had the benefit of a number of years of reviews of prior or similar agreements during which lengthy discussions took place between the Board members and Dreyfus representatives. Certain aspects of the arrangements may receive greater scrutiny in some years than in others, and the Board members’ conclusions may be based, in part, on their consideration of the same or similar arrangements in prior years. The Board members determined that renewal of the Agreement was in the best interests of the fund and its shareholders.

Item 2. Code of Ethics.

Not applicable.

Item 3. Audit Committee Financial Expert.

Not applicable.

Item 4. Principal Accountant Fees and Services.

Not applicable.

Item 5. Audit Committee of Listed Registrants.

Not applicable.

Item 6. Investments.

(a) 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 Companies and Affiliated Purchasers.

Not applicable. [CLOSED END FUNDS ONLY]

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

There have been no material changes to the procedures applicable to Item 10.

Item 11. Controls and Procedures.

(a) The Registrant's principal executive and principal financial officers have concluded, based on their evaluation of the Registrant's disclosure controls and procedures as of a date within 90 days of the filing date of this report, that the Registrant's disclosure controls and procedures are reasonably designed to ensure that information required to be disclosed by the Registrant on Form N-CSR is recorded, processed, summarized and reported within the required time periods and that information required to be disclosed by the Registrant in the reports that it files or submits on Form N-CSR is accumulated and communicated to the Registrant's management, including its principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosure.

(b) There were no changes to the Registrant's internal control over financial reporting that occurred during the 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) Not applicable.

(a)(2) Certifications of principal executive and principal financial officers as required by Rule 30a-2(a) under the Investment Company Act of 1940.

(a)(3) Not applicable.

(b) Certification of principal executive and principal financial officers as required by Rule 30a-2(b) under the Investment Company Act of 1940.

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.

Dreyfus BASIC U.S. Government Money Market Fund

By: /s/ Bradley J. Skapyak
Bradley J. Skapyak, President
Date:	October 24, 2011

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/ Bradley J. Skapyak
Bradley J. Skapyak, President
Date:	October 24, 2011

By: /s/ James Windels
James Windels, Treasurer
Date:	October 24, 2011

EXHIBIT INDEX

(a)(2) Certifications of principal executive and principal financial officers as required by Rule 30a-2(a) under the Investment Company Act of 1940. (EX-99.CERT)

(b) Certification of principal executive and principal financial officers as required by Rule 30a-2(b) under the Investment Company Act of 1940. (EX-99.906CERT)

Dreyfus Basic U S Government Money Market Fund Inactive N-CSRSCertified semi-annual shareholder report (management investment company)