Fidelity Money Market Trust N-CSR Certified 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 811-2861

Fidelity Money Market Trust
(Exact name of registrant as specified in charter)

82 Devonshire St., Boston, Massachusetts 02109
(Address of principal executive offices)       (Zip code)

Scott C. Goebel, Secretary

82 Devonshire St.

Boston, Massachusetts 02109
(Name and address of agent for service)

Registrant's telephone number, including area code: 617-563-7000

Date of fiscal year end:	August 31
Date of reporting period:	August 31, 2009

Item 1. Reports to Stockholders

Fidelity Money Market Trust
Retirement Government Money Market Portfolio

Annual Report

August 31, 2009

(2_fidelity_logos) (Registered_Trademark)

Contents

Shareholder Expense Example	<Click Here>	An example of shareholder expenses.
Investment Changes/ Performance	<Click Here>	A summary of major shifts in the fund's investments over the past six months and one year, and performance information.
Investments	<Click Here>	A complete list of the fund's investments.
Financial Statements	<Click Here>	Statements of assets and liabilities, operations, and changes in net assets, as well as financial highlights.
Notes	<Click Here>	Notes to the financial statements.
Report of Independent Registered Public Accounting Firm	<Click Here>
Trustees and Officers	<Click Here>
Distributions	<Click Here>
Board Approval of Investment Advisory Contracts and Management Fees	<Click Here>

To view a fund's proxy voting guidelines and proxy voting record for the 12-month period ended June 30, visit http://www.fidelity.com/proxyvotingresults or visit the Securities and Exchange Commission's (SEC) web site at http://www.sec.gov. You may also call 1-800-544-8544 to request a free copy of the proxy voting guidelines.

Standard & Poor's, S&P and S&P 500 are registered service marks of The McGraw-Hill Companies, Inc. and have been licensed for use by Fidelity Distributors Corporation.

Other third party marks appearing herein are the property of their respective owners.

All other marks appearing herein are registered or unregistered trademarks or service marks of FMR LLC or an affiliated company.

The fund seeks to obtain as high a level of current income as is consistent with the preservation of capital and liquidity by investing in high-quality, short-term money market securities issued or guaranteed as to principal and interest by the U.S. Government, or by any of its agencies or instrumentalities.

Annual Report

Investments in the fund are neither insured nor guaranteed by the U.S. Government, and there can be no assurance that the fund will maintain a stable $1.00 share price.

This report and the financial statements contained herein are submitted for the general information of the shareholders of the fund. This report is not authorized for distribution to prospective investors in the fund unless preceded or accompanied by an effective prospectus.

A fund files its complete schedule of portfolio holdings with the SEC for the first and third quarters of each fiscal year on Form N-Q. Forms N-Q are available on the SEC's web site at http://www.sec.gov. A fund's Forms N-Q may be reviewed and copied at the SEC's Public Reference Room in Washington, DC. Information regarding the operation of the SEC's Public Reference Room may be obtained by calling 1-800-SEC-0330. For a complete list of a fund's portfolio holdings, view the most recent holdings listing, semiannual report, or annual report on Fidelity's web site at http://www.fidelity.com or http://www.advisor.fidelity.com, as applicable.

NOT FDIC INSURED · MAY LOSE VALUE · NO BANK GUARANTEE

Neither the fund nor Fidelity Distributors Corporation is a bank.

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Shareholder Expense Example

As a shareholder of the Fund, you incur two types of costs: (1) transaction costs, and (2) ongoing costs, including management fees and other Fund expenses. This Example is 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 Example is based on an investment of $1,000 invested at the beginning of the period and held for the entire period (March 1, 2009 to August 31, 2009).

Actual Expenses

The first line of the accompanying table provides information about actual account values and actual expenses. You may use the information in this line, together with the amount you invested, to estimate the expenses that you paid over the period. Simply divide your account value by $1,000.00 (for example, an $8,600 account value divided by $1,000.00 = 8.6), then multiply the result by the number in the first line 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 line of the accompanying table provides information about hypothetical account values and hypothetical expenses based on the Fund's actual expense ratio and an assumed rate of return of 5% per year before expenses, which is not the Fund's 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 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 transaction costs. Therefore, the second line of the table is useful in comparing ongoing costs only, and will not help you determine the relative total costs of owning different funds.

	Annualized Expense Ratio	Beginning Account Value March 1, 2009	Ending Account Value August 31, 2009	Expenses Paid During Period* March 1, 2009 to August 31, 2009
Actual	.43%	$ 1,000.00	$ 1,001.50	$ 2.17
Hypothetical (5% return per year before expenses)		$ 1,000.00	$ 1,023.04	$ 2.19

* Expenses are equal to the Fund's annualized expense ratio, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period).

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Investment Changes/Performance (Unaudited)

Maturity Diversification
Days	% of fund's investments 8/31/09	% of fund's investments 2/28/09	% of fund's investments 8/31/08
0 - 30	59.0	44.4	57.4
31 - 90	17.7	33.0	21.7
91 - 180	7.8	11.9	11.5
181 - 397	15.5	10.7	9.4
Weighted Average Maturity
	8/31/09	2/28/09	8/31/08
Retirement Government Money Market Portfolio	69 Days	68 Days	60 Days
All Taxable Money Market Funds Average*	52 Days	49 Days	44 Days

Asset Allocation (% of fund's net assets)
As of August 31, 2009		As of February 28, 2009
	Federal Agency Issues 48.5%		Federal Agency Issues 70.8%
	U.S. Treasury Obligations 13.7%		U.S. Treasury Obligations 6.3%
	Other Government Related† 2.8%		Other Government Related 0.0%
	Repurchase Agreements 34.9%		Repurchase Agreements 24.4%
	Net Other Assets 0.1%		Net Other Assets** (1.5)%

** Net Other Assets are not included in the pie chart.

^† Includes Federal Financing Bank Supported Student Loan Short-Term Notes

Current and Historical Seven-Day Yields

	9/1/09	6/2/09	3/3/09	12/2/08	9/2/08
Retirement Government Money Market Portfolio	0.04%	0.30%	0.55%	1.41%	2.08%

Yield refers to the income paid by the fund over a given period. Yields for money market funds are usually for seven-day periods, as they are here, though they are expressed as annual percentage rates. Past performance is no guarantee of future results. Yield will vary and it is possible to lose money by investing in the fund.

*Source: iMoneyNet, Inc.

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Investments August 31, 2009

Showing Percentage of Net Assets

U.S. Government and Government Agency Obligations - 2.8%
	Due Date	Yield (a)	Principal Amount (000s)	Value (000s)
Other Government Related - 2.8%
Straight-A Funding LLC (Liquidity Facility Federal Financing Bank)
	11/19/09 to 11/20/09	0.26% (b)	$ 149,000	$ 148,918
Federal Agencies - 48.5%
Fannie Mae - 10.6%
	9/1/09 to 2/22/10	0.39 to 1.62 (c)	560,995	560,554
Federal Home Loan Bank - 23.7%
	9/4/09 to 8/17/10	0.18 to 2.66 (c)	1,245,980	1,246,082
Freddie Mac - 14.2%
	9/3/09 to 5/5/10	0.17 to 1.24 (c)	747,000	747,144
TOTAL FEDERAL AGENCIES				2,553,780
U.S. Treasury Obligations - 13.7%
U.S. Treasury Bills - 11.5%
	10/22/09 to 8/26/10	0.35 to 1.01	610,592	608,450
U.S. Treasury Notes - 2.2%
	5/31/10 to 6/30/10	0.48 to 0.60	112,000	113,750
TOTAL U.S. TREASURY OBLIGATIONS				722,200

Repurchase Agreements - 34.9%
	Maturity Amount (000s)
In a joint trading account at 0.22% dated 8/31/09 due 9/1/09 (Collateralized by U.S. Government Obligations) #	$ 1,632,898		1,632,888
With:
Barclays Capital, Inc. at 0.22%, dated 8/10/09 due 9/30/09 (Collateralized by U.S. Government Obligations valued at $17,342,796, 0%, 11/27/09)	17,005		17,000
Deutsche Bank Securities, Inc. at 0.22%, dated 8/4/09 due 10/2/09 (Collateralized by U.S. Government Obligations valued at $72,432,392, 7%, 10/1/38)	71,026		71,000
Repurchase Agreements - continued
	Maturity Amount (000s)		Value (000s)
With: - continued
ING Financial Markets LLC at:
0.23%, dated 8/17/09 due 10/16/09 (Collateralized by U.S. Government Obligations valued at $72,107,248, 0.66% - 6%, 12/15/16 - 7/25/48)	$ 70,027		$ 70,000
0.27%, dated 7/20/09 due 9/18/09 (Collateralized by U.S. Government Obligations valued at $52,548,664, 6%, 5/15/35 - 11/15/35)	51,023		51,000
TOTAL REPURCHASE AGREEMENTS		1,841,888
TOTAL INVESTMENT PORTFOLIO - 99.9% (Cost $5,266,786)			5,266,786
NET OTHER ASSETS - 0.1%			3,452
NET ASSETS - 100%		$ 5,270,238

Legend

(a) Yield represents either the annualized yield at the date of purchase, or the stated coupon rate, or, for floating rate securities, the rate at period end.

(b) The Federal Financing Bank, an instrumentality of the U.S. Government acting under the supervision of the Secretary of the Treasury (FFB), has entered into a Liquidity Loan Agreement with Straight-A Funding LLC (Issuer), pursuant to which the FFB has committed, subject to certain conditions, to provide financing to the Issuer to cover any payment deficiencies in respect of notes on their legal final maturity dates. At the end of the period, these securities amounted to $148,918,000 or 2.8% of net assets.

(c) Coupon rates for floating and adjustable rate securities reflect the rates in effect at period end. Due dates for these security types are the next interest rate reset date or, when applicable, the final maturity date.

# Additional information on each counterparty to the repurchase agreement is as follows:

Repurchase Agreement / Counterparty	Value (Amounts in thousands)
$1,632,888,000 due 9/01/09 at 0.22%
BNP Paribas Securities Corp.	$ 126,529
Banc of America Securities LLC	140,981
Bank of America, NA	216,907
Barclays Capital, Inc.	176,237
Citigroup Global Markets, Inc.	108,453
Credit Suisse Securities (USA) LLC	72,302
Deutsche Bank Securities, Inc.	117,491
Greenwich Capital Markets, Inc.	36,151
ING Financial Markets LLC	75,917
J.P. Morgan Securities, Inc.	237,864
Merrill Lynch Government Securities, Inc.	18,076
Mizuho Securities USA, Inc.	95,801
RBC Capital Markets Corp.	9,038
Societe Generale, New York Branch	72,302
UBS Securities LLC	110,763
Wachovia Capital Markets LLC	18,076
	$ 1,632,888

Other Information

All investments are categorized as Level 2 under the Fair Value Hierarchy. The inputs or methodology used for valuing securities may not be an indication of the risk associated with investing in those securities. For more information on valuation inputs, please refer to the Security Valuation section in the accompanying Notes to Financial Statements.

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements

Statement of Assets and Liabilities

Amounts in thousands (except per-share amount)	August 31, 2009
Assets
Investment in securities, at value (including repurchase agreements of $1,841,888) - See accompanying schedule: Unaffiliated issuers (cost $5,266,786)		$ 5,266,786
Receivable for fund shares sold		16,111
Interest receivable		4,693
Total assets		5,287,590
Liabilities
Payable for fund shares redeemed	$ 15,488
Accrued management fee	1,861
Other affiliated payables	1
Other payables and accrued expenses	2
Total liabilities		17,352
Net Assets		$ 5,270,238
Net Assets consist of:
Paid in capital		$ 5,269,522
Accumulated undistributed net realized gain (loss) on investments		716
Net Assets, for 5,269,139 shares outstanding		$ 5,270,238
Net Asset Value, offering price and redemption price per share ($5,270,238 ÷ 5,269,139 shares)		$ 1.00

See accompanying notes which are an integral part of the financial statements.

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Financial Statements - continued

Statement of Operations

Amounts in thousands	Year ended August 31, 2009
Investment Income
Interest		$ 70,170
Expenses
Management fee	$ 22,890
Independent trustees' compensation	20
Money Market Guarantee Program Fee	1,275
Total expenses before reductions	24,185
Expense reductions	(19)	24,166
Net investment income		46,004
Realized and Unrealized Gain (Loss) Net realized gain (loss) on:
Investment securities:
Unaffiliated issuers		720
Net increase in net assets resulting from operations		$ 46,724

See accompanying notes which are an integral part of the financial statements.

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Statement of Changes in Net Assets

Amounts in thousands	Year ended August 31, 2009	Year ended August 31, 2008
Increase (Decrease) in Net Assets
Operations
Net investment income	$ 46,004	$ 159,932
Net realized gain (loss)	720	669
Net increase in net assets resulting from operations	46,724	160,601
Distributions to shareholders from net investment income	(46,000)	(159,939)
Share transactions at net asset value of $1.00 per share Proceeds from sales of shares	3,124,889	2,950,718
Reinvestment of distributions	45,988	159,909
Cost of shares redeemed	(2,917,192)	(2,828,280)
Net increase (decrease) in net assets and shares resulting from share transactions	253,685	282,347
Total increase (decrease) in net assets	254,409	283,009
Net Assets
Beginning of period	5,015,829	4,732,820
End of period	$ 5,270,238	$ 5,015,829

See accompanying notes which are an integral part of the financial statements.

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Financial Highlights

Years ended August 31,	2009	2008	2007	2006	2005
Selected Per-Share Data
Net asset value, beginning of period	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Income from Investment Operations
Net investment income	.009	.033	.049	.042	.021
Distributions from net investment income	(.009)	(.033)	(.049)	(.042)	(.021)
Net asset value, end of period	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Total Return A	.86%	3.35%	5.06%	4.25%	2.17%
Ratios to Average Net Assets B
Expenses before reductions	.44%	.42%	.42%	.42%	.42%
Expenses net of fee waivers, if any	.44%	.42%	.42%	.42%	.42%
Expenses net of all reductions	.44%	.41%	.39%	.40%	.41%
Net investment income	.84%	3.28%	4.95%	4.18%	2.13%
Supplemental Data
Net assets, end of period (in millions)	$ 5,270	$ 5,016	$ 4,733	$ 4,826	$ 4,740

^A Total returns would have been lower had certain expenses not been reduced during the periods shown.

^B Expense ratios reflect operating expenses of the Fund. Expenses before reductions do not reflect amounts reimbursed by the investment adviser or expense offset arrangements and do not represent the amount paid by the Fund during periods when reimbursements or reductions occur. Expenses net of fee waivers reflect expenses after reimbursement by the investment adviser but prior to reductions from expense offset arrangements. Expenses net of all reductions represent the net expenses paid by the Fund.

See accompanying notes which are an integral part of the financial statements.

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Notes to Financial Statements

For the period ended August 31, 2009

(Amounts in thousands except ratios)

1. Organization.

Retirement Government Money Market Portfolio (the Fund) is a fund of Fidelity Money Market Trust (the trust) and is authorized to issue an unlimited number of shares. The trust is registered under the Investment Company Act of 1940, as amended (the 1940 Act), as an open-end management investment company organized as a Delaware statutory trust.

2. Significant Accounting Policies.

The financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America, which require management to make certain estimates and assumptions at the date of the financial statements. Actual results could differ from those estimates. Events or transactions occurring after period end through the date that the financial statements were issued, October 13, 2009, have been evaluated in the preparation of the financial statements. The following summarizes the significant accounting policies of the Fund:

Security Valuation. As permitted by compliance with certain conditions under Rule 2a-7 of the 1940 Act, securities are valued at amortized cost, which approximates value. Generally Accepted Accounting Principles (GAAP) establishes a disclosure hierarchy that categorizes the inputs to valuation techniques used to value assets and liabilities at measurement date. These inputs are classified into three levels. Level 1 includes readily available unadjusted quoted prices in active markets for identical assets or liabilities. Level 2 includes observable inputs other than quoted prices included in Level 1 that are observable either directly or indirectly. Level 3 includes unobservable inputs when market prices are not readily available or reliable.

Investment Transactions and Income. The net asset value per share for processing shareholder transactions is calculated as of the close of business of the New York Stock Exchange (NYSE), normally 4:00 p.m. Eastern time. Security transactions are accounted for as of trade date. Gains and losses on securities sold are determined on the basis of identified cost. Interest income is accrued as earned. Interest income includes coupon interest and amortization of premium and accretion of discount on debt securities.

Expenses. Most expenses of the trust can be directly attributed to a fund. Expenses which cannot be directly attributed are apportioned among each Fund in the trust. Expense estimates are accrued in the period to which they relate and adjustments are made when actual amounts are known.

The Fund participated in the U.S. Treasury Department's Temporary Guarantee Program for Money Market Funds (the "Program") through April 30, 2009. The Fund paid the U.S. Treasury Department fees equal to 0.025% based on the number of shares outstanding as of September 19, 2008 to participate in the Program through April 30, 2009. The expense was borne by the Fund without regard to any expense limitation in effect for the Fund.

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Notes to Financial Statements - continued

(Amounts in thousands except ratios)

2. Significant Accounting Policies - continued

Income Tax Information and Distributions to Shareholders. Each year, the Fund intends to qualify as a regulated investment company by distributing substantially all of its taxable income and realized gains under Subchapter M of the Internal Revenue Code and filing its U.S. federal tax return. As a result, no provision for income taxes is required. The Fund is subject to the provisions of FASB Interpretation No. 48, Accounting for Uncertainties in Income Taxes (FIN 48). FIN 48 sets forth a minimum threshold for financial statement recognition of the benefit of a tax position taken or expected to be taken in a tax return. There are no unrecognized tax benefits in the accompanying financial statements. A Fund's federal tax return is subject to examination by the Internal Revenue Service (IRS) for a period of three years.

Dividends are declared daily and paid monthly from net investment income. Distributions from realized gains, if any, are recorded on the ex-dividend date. Income and capital gain distributions are determined in accordance with income tax regulations, which may differ from generally accepted accounting principles. In addition, the Fund will claim a portion of the payment made to redeeming shareholders as a distribution for income tax purposes.

Capital accounts within the financial statements are adjusted for permanent book-tax differences. These adjustments have no impact on net assets or the results of operations. Temporary book-tax differences will reverse in a subsequent period.

Book-tax differences are primarily due to deferred trustees compensation, capital loss carryforwards and losses deferred due to wash sales.

The tax-basis components of distributable earnings and the federal tax cost as of period end were as follows:

Unrealized appreciation	$ -
Unrealized depreciation	-
Net unrealized appreciation (depreciation)	$ -
Undistributed ordinary income	$ 717
Cost for federal income tax purposes	$ 5,266,786

The tax character of distributions paid was as follows:

	August 31, 2009	August 31, 2008
Ordinary Income	$ 46,000	$ 159,939

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3. Operating Policies.

Repurchase Agreements. Fidelity Management & Research Company (FMR) has received an Exemptive Order from the Securities and Exchange Commission (the SEC) which permits the Fund and other affiliated entities of FMR to transfer uninvested cash balances into joint trading accounts which are then invested in repurchase agreements. The Fund may also invest directly with institutions in repurchase agreements. Repurchase agreements are collateralized by government or non-government securities. Upon settlement date, collateral is held in segregated accounts with custodian banks and may be obtained in the event of a default of the counterparty. The Fund monitors, on a daily basis, the value of the collateral to ensure it is at least equal to the principal amount of the repurchase agreement (including accrued interest). In the event of a default by the counterparty, realization of the collateral proceeds could be delayed, during which time the value of the collateral may decline.

Reverse Repurchase Agreements. To enhance its yield, the Fund may enter into reverse repurchase agreements whereby the Fund transfers securities to a counterparty who then agrees to transfer them back to the Fund at a future date and agreed upon price, reflecting a rate of interest below market rate. The Fund receives cash proceeds, which are invested in other securities, and agrees to repay the proceeds plus accrued interest in return for the same securities transferred. The Fund continues to receive interest payments on the transferred securities during the term of the reverse repurchase agreement. During the period that a reverse repurchase agreement is outstanding, the Fund identifies cash and liquid securities as segregated in its custodian records with a value at least equal to its obligation under the agreement. If the counterparty defaults on its obligation, because of insolvency or other reasons, the Fund could experience delays and costs in recovering the security or in gaining access to the collateral. The average daily balance during the period for which reverse repurchase agreements were outstanding amounted to $10,568. The weighted average interest rate was 0.06%. At period end, there were no reverse repurchase agreements outstanding.

4. Fees and Other Transactions with Affiliates.

Management Fee. FMR and its affiliates provide the Fund with investment management related services for which the Fund pays a monthly management fee that is based on an annual rate of .42% of the Fund's average net assets. FMR pays all other expenses, except the compensation of the independent Trustees and certain exceptions such as interest expense. The management fee paid to FMR by the Fund is reduced by an amount equal to the fees and expenses paid by the Fund to the independent Trustees.

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Notes to Financial Statements - continued

(Amounts in thousands except ratios)

5. Expense Reductions.

Through arrangements with the Fund's custodian and transfer agent, credits realized as a result of uninvested cash balances were used to reduce the Fund's management fee. During the period, these credits reduced the Fund's management fee by $19.

6. Other.

The Fund's organizational documents provide former and current 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.

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Report of Independent Registered Public Accounting Firm

To the Trustees of Fidelity Money Market Trust and the Shareholders of Retirement Government Money Market Portfolio:

In our opinion, the accompanying statement of assets and liabilities, including the schedule of investments, and the related statements of operations and of changes in net assets and the financial highlights present fairly, in all material respects, the financial position of Retirement Government Money Market Portfolio (a fund of Fidelity Money Market Trust) at August 31, 2009, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period then ended and the financial highlights for each of the five years in the period then ended, in conformity with accounting principles generally accepted in the United States of America. These financial statements and financial highlights (hereafter referred to as "financial statements") are the responsibility of the Retirement Government Money Market Portfolio's management. Our responsibility is to express an opinion on these financial statements based on our audits. We conducted our audits of these financial statements 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 are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits, which included confirmation of securities at August 31, 2009 by correspondence with the custodian and brokers, provide a reasonable basis for our opinion.

/s/ PricewaterhouseCoopers LLP

PricewaterhouseCoopers LLP

Boston, Massachusetts

October 13, 2009

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Trustees and Officers

The Trustees and executive officers of the trust and fund, as applicable, are listed below. The Board of Trustees governs the fund and is responsible for protecting the interests of shareholders. The Trustees are experienced executives who meet periodically throughout the year to oversee the fund's activities, review contractual arrangements with companies that provide services to the fund, and review the fund's performance. Except for James C. Curvey, each of the Trustees oversees 187 funds advised by FMR or an affiliate. Mr. Curvey oversees 407 funds advised by FMR or an affiliate.

The Trustees hold office without limit in time except that (a) any Trustee may resign; (b) any Trustee may be removed by written instrument, signed by at least two-thirds of the number of Trustees prior to such removal; (c) any Trustee who requests to be retired or who has become incapacitated by illness or injury may be retired by written instrument signed by a majority of the other Trustees; and (d) any Trustee may be removed at any special meeting of shareholders by a two-thirds vote of the outstanding voting securities of the trust. Each Trustee who is not an interested person (as defined in the 1940 Act) (Independent Trustee), shall retire not later than the last day of the calendar year in which his or her 72nd birthday occurs. The Independent Trustees may waive this mandatory retirement age policy with respect to individual Trustees. The executive officers hold office without limit in time, except that any officer may resign or may be removed by a vote of a majority of the Trustees at any regular meeting or any special meeting of the Trustees. Except as indicated, each individual has held the office shown or other offices in the same company for the past five years.

Interested Trustees*:

The fund's Statement of Additional Information (SAI) includes more information about the Trustees. To request a free copy, call Fidelity at 1-800-544-8544.

Correspondence intended for each Trustee who is an interested person may be sent to Fidelity Investments, 82 Devonshire Street, Boston, Massachusetts 02109.

Name, Age; Principal Occupation
Abigail P. Johnson (47)
	Year of Election or Appointment: 2009 Ms. Johnson is Trustee and Chairman of the Board of Trustees of certain Trusts. Ms. Johnson serves as President of Personal and Workplace Investing (2005-present). Ms. Johnson is a Director of FMR LLC. Previously, Ms. Johnson served as President and a Director of FMR (2001-2005), a Trustee of other investment companies advised by FMR, Fidelity Investments Money Management, Inc., and FMR Co., Inc. (2001-2005), Senior Vice President of the Fidelity funds (2001-2005), and managed a number of Fidelity funds. Ms. Abigail P. Johnson and Mr. Arthur E. Johnson are not related.
James C. Curvey (74)
	Year of Election or Appointment: 2007 Mr. Curvey also serves as Trustee (2007-present) of other investment companies advised by FMR. Mr. Curvey is a Director of FMR and FMR Co., Inc. (2007-present). Mr. Curvey is also Vice Chairman (2006- present) and Director of FMR LLC. In addition, Mr. Curvey serves as an Overseer for the Boston Symphony Orchestra and a member of the Trustees of Villanova University.

* Trustees have been determined to be "Interested Trustees" by virtue of, among other things, their affiliation with the trust or various entities under common control with FMR.

Independent Trustees:

Correspondence intended for each Independent Trustee (that is, the Trustees other than the Interested Trustees) may be sent to Fidelity Investments, P.O. Box 55235, Boston, Massachusetts 02205-5235.

Name, Age; Principal Occupation
Albert R. Gamper, Jr. (67)
	Year of Election or Appointment: 2006 Prior to his retirement in December 2004, Mr. Gamper served as Chairman of the Board of CIT Group Inc. (commercial finance). During his tenure with CIT Group Inc. Mr. Gamper served in numerous senior management positions, including Chairman (1987-1989; 1999-2001; 2002-2004), Chief Executive Officer (1987-2004), and President. Mr. Gamper currently serves as a member of the Board of Directors of Public Service Enterprise Group (utilities), a member of the Board of Trustees, Rutgers University (2004-present), and Chairman of the Board of Saint Barnabas Health Care System. Previously, Mr. Gamper served as Chairman of the Board of Governors, Rutgers University (2004-2007).
Arthur E. Johnson (62)
	Year of Election or Appointment: 2008 Mr. Johnson serves as a member of the Board of Directors of Eaton Corporation (diversified power management, 2009-present) and AGL Resources, Inc. (holding company). Previously, Mr. Johnson served as Senior Vice President of Corporate Strategic Development of Lockheed Martin Corporation (defense contractor, 1999-2009), and on the Board of Directors of IKON Office Solutions, Inc. (1999-2008). Mr. Arthur E. Johnson and Ms. Abigail P. Johnson are not related.
Michael E. Kenneally (55)
	Year of Election or Appointment: 2009 Mr. Kenneally also serves as Trustee (2009-present) or Member of the Advisory Board (2008-present) of other Fidelity Fixed Income and Asset Allocation Funds. Previously, Mr. Kenneally served as Chairman and Global Chief Executive Officer of Credit Suisse Asset Management (2003-2005). Mr. Kenneally was a Director of The Credit Suisse Funds (U.S. Mutual Fund, 2004-2008) and was awarded the Chartered Financial Analyst (CFA) designation in 1991.
James H. Keyes (68)
	Year of Election or Appointment: 2007 Mr. Keyes serves as a member of the Boards of Navistar International Corporation (manufacture and sale of trucks, buses, and diesel engines) and Pitney Bowes, Inc. (integrated mail, messaging, and document management solutions). Previously, Mr. Keyes served as a member of the Board of LSI Logic Corporation (semiconductor technologies, 1984-2008).
Marie L. Knowles (62)
	Year of Election or Appointment: 2001 Prior to Ms. Knowles' retirement in June 2000, she served as Executive Vice President and Chief Financial Officer of Atlantic Richfield Company (ARCO) (diversified energy, 1996-2000). From 1993 to 1996, she was a Senior Vice President of ARCO and President of ARCO Transportation Company. She served as a Director of ARCO from 1996 to 1998. Ms. Knowles currently serves as a Director of McKesson Corporation (healthcare service). Ms. Knowles is an Honorary Trustee of the Brookings Institution and a member of the Board of the Catalina Island Conservancy and of the Santa Catalina Island Company (2009-present). She also serves as a member of the Advisory Board for the School of Engineering of the University of Southern California and the Foundation Board of the School of Architecture at the University of Virginia (2007-present). Previously, Ms. Knowles served as a Director of Phelps Dodge Corporation (copper mining and manufacturing, 1994-2007).
Kenneth L. Wolfe (70)
	Year of Election or Appointment: 2005 Mr. Wolfe served as Chairman and a Director (2007-2009) and Chairman and Chief Executive Officer of Hershey Foods Corporation, and as a member of the Boards of Adelphia Communications Corporation (telecommunications, 2003-2006), Bausch & Lomb, Inc. (medical/pharmaceutical, 1993-2007), and Revlon, Inc. (2004-2009).

Annual Report

Trustees and Officers - continued

Executive Officers:

Correspondence intended for each executive officer may be sent to Fidelity Investments, 82 Devonshire Street, Boston, Massachusetts 02109.

Name, Age; Principal Occupation
John R. Hebble (51)
	Year of Election or Appointment: 2008 President and Treasurer of Fidelity's Fixed Income and Asset Allocation Funds. Mr. Hebble also serves as Assistant Treasurer of other Fidelity funds (2009-present) and is an employee of Fidelity Investments.
Boyce I. Greer (53)
	Year of Election or Appointment: 2005 or 2006 Vice President of Fidelity's Fixed Income Funds (2006) and Asset Allocation Funds (2005). Mr. Greer is also a Trustee of other investment companies advised by FMR. Mr. Greer is President of the Asset Allocation Division (2008-present), President and a Director of Strategic Advisers, Inc. (2008-present), President and a Director of Fidelity Investments Money Management, Inc. (2007-present), and an Executive Vice President of FMR and FMR Co., Inc. (2005-present). Previously, Mr. Greer served as a Director and Managing Director of Strategic Advisers, Inc. (2002-2005).
Charles S. Morrison (48)
	Year of Election or Appointment: 2005 Vice President of Fidelity's Money Market Funds. Mr. Morrison also serves as President, Money Market Group Leader of FMR (2009-present), and as Executive Vice President of Fidelity Management & Research (U.K.) Inc. (2008-present). Previously, Mr. Morrison served as Senior Vice President, Money Market Group of FMR (2004-2009), Vice President of Fidelity's Bond Funds and certain Balanced, and Asset Allocation Funds.
Scott C. Goebel (41)
	Year of Election or Appointment: 2008 Secretary and Chief Legal Officer (CLO) of the Fidelity funds. Mr. Goebel also serves as General Counsel, Secretary, and Senior Vice President of FMR (2008-present) and FMR Co., Inc. (2008-present); Deputy General Counsel of FMR LLC; Chief Legal Officer of Fidelity Management & Research (Hong Kong) Limited (2008-present) and Assistant Secretary of Fidelity Management & Research (Japan) Inc. (2008-present), Fidelity Investments Money Management, Inc. (2008-present), Fidelity Management & Research (U.K.) Inc. (2008-present), and Fidelity Research and Analysis Company (2008-present). Previously, Mr. Goebel served as Assistant Secretary of the Funds (2007-2008) and as Vice President and Secretary of Fidelity Distributors Corporation (FDC) (2005-2007).
Holly C. Laurent (55)
	Year of Election or Appointment: 2008 Anti-Money Laundering (AML) Officer of the Fidelity funds. Ms. Laurent is an employee of Fidelity Investments. Previously, Ms. Laurent was Senior Vice President and Head of Legal for Fidelity Business Services India Pvt. Ltd. (2006-2008), and Senior Vice President, Deputy General Counsel and Group Head for FMR LLC (2005-2006).
Christine Reynolds (50)
	Year of Election or Appointment: 2008 Chief Financial Officer of the Fidelity funds. Ms. Reynolds became President of Fidelity Pricing and Cash Management Services (FPCMS) in August 2008. Ms. Reynolds served as Chief Operating Officer of FPCMS (2007-2008). Previously, Ms. Reynolds served as President, Treasurer, and Anti-Money Laundering officer of the Fidelity funds (2004-2007).
Michael H. Whitaker (42)
	Year of Election or Appointment: 2008 Chief Compliance Officer of Fidelity's Fixed Income and Asset Allocation Funds. Mr. Whitaker is an employee of Fidelity Investments (2007-present). Prior to joining Fidelity Investments, Mr. Whitaker worked at MFS Investment Management where he served as Senior Vice President and Chief Compliance Officer (2004-2006), and Assistant General Counsel.
Jeffrey S. Christian (47)
	Year of Election or Appointment: 2009 Deputy Treasurer of the Fidelity funds. Mr. Christian also serves as Chief Financial Officer of other Fidelity funds (2008-present) and is an employee of Fidelity Investments. Previously, Mr. Christian served as Senior Vice President of Fidelity Pricing and Cash Management Services (FPCMS) (2004-2009) and as Vice President of Business Analysis (2003-2004).
Bryan A. Mehrmann (48)
	Year of Election or Appointment: 2005 Deputy Treasurer of the Fidelity funds. Mr. Mehrmann is an employee of Fidelity Investments. Previously, Mr. Mehrmann served as Vice President of Fidelity Investments Institutional Services Group (FIIS)/Fidelity Investments Institutional Operations Company, Inc. (FIIOC) Client Services (1998-2004).
Stephanie J. Dorsey (40)
	Year of Election or Appointment: 2008 Deputy Treasurer of Fidelity's Fixed Income and Asset Allocation Funds. Ms. Dorsey is an employee of Fidelity Investments (2008-present). Previously, Ms. Dorsey served as Treasurer (2004-2008) of the JPMorgan Mutual Funds and Vice President (2004-2008) of JPMorgan Chase Bank.
Paul M. Murphy (62)
	Year of Election or Appointment: 2007 Assistant Treasurer of the Fidelity funds. Mr. Murphy is an employee of Fidelity Investments. Previously, Mr. Murphy served as Chief Financial Officer of the Fidelity funds (2005-2006), Vice President and Associate General Counsel of FMR (2007), and Senior Vice President of Fidelity Pricing and Cash Management Services (FPCMS) (1994-2007).
Kenneth B. Robins (40)
	Year of Election or Appointment: 2009 Assistant Treasurer of the Fidelity Fixed Income and Asset Allocation Funds. Mr. Robins also serves as President and Treasurer of other Fidelity funds and is an employee of Fidelity Investments (2004-present). Before joining Fidelity Investments, Mr. Robins worked at KPMG LLP, where he was a partner in KPMG's department of professional practice (2002-2004).
Gary W. Ryan (51)
	Year of Election or Appointment: 2005 Assistant Treasurer of the Fidelity funds. Mr. Ryan is an employee of Fidelity Investments. Previously, Mr. Ryan served as Vice President of Fund Reporting in Fidelity Pricing and Cash Management Services (FPCMS) (1999-2005).

Annual Report

Distributions (Unaudited)

The fund hereby designates as a capital gain dividend with respect to the taxable year ended August 31, 2009, $68,737, or, if subsequently determined to be different, the net capital gain of such year.

A total of 47.27% of the dividends distributed during the fiscal year was derived from interest on U.S. Government securities which is generally exempt from state income tax.

The fund designates $14,827,459 of distributions paid during the period January 1, 2009 to August 31, 2009 as qualifying to be taxed as interest-related dividends for nonresident alien shareholders.

The fund will notify shareholders in January 2010 of amounts for use in preparing 2009 income tax returns.

Annual Report

Board Approval of Investment Advisory Contracts and Management Fees

Fidelity Retirement Government Money Market Portfolio

On May 21, 2009, the Board of Trustees, including the Independent Trustees (together, the Board), voted to continue the management contract and subadvisory agreements (together, the Advisory Contracts) for the fund for four months, through September 30, 2009, in connection with the reorganization of the Board's new meeting schedule. The Board considered that the contractual terms of and fees payable under the fund's Advisory Contracts involve no changes in (i) the investment process or strategies employed in the management of the fund's assets; (ii) the nature or level of services provided under the fund's Advisory Contracts; or (iii) the day-to-day management of the fund or the persons primarily responsible for such management. The Board concluded that the fund's Advisory Contracts are fair and reasonable, and that the fund's Advisory Contracts should be renewed, without modification, through September 30, 2009, with the understanding that the Board will consider their renewal in September 2009.

Annual Report

Investment Adviser

Fidelity Management &
Research Company
Boston, MA

Investment Sub-Advisers

Fidelity Investments Money
Management, Inc.

FIL Investment Advisors

FIL Investment Advisors
(U.K.) Ltd.

Fidelity Research & Analysis Company

Fidelity Management & Research
(U.K.) Inc.

Fidelity Management & Research
(Hong Kong) Limited

Fidelity Management & Research
(Japan) Inc.

General Distributor

Fidelity Distributors Corporation

Boston, MA

Transfer and Service Agents

Fidelity Investments Institutional
Operations Company, Inc.
Boston, MA

Fidelity Service Company, Inc.
Boston, MA

Custodian

JPMorgan Chase Bank

New York, NY

RGM-ANN-1009
1.768777.107

Fidelity Money Market Trust
Retirement Money Market Portfolio

Annual Report

August 31, 2009

(2_fidelity_logos) (Registered_Trademark)

Contents

Shareholder Expense Example	<Click Here>	An example of shareholder expenses.
Investment Changes/ Performance	<Click Here>	A summary of major shifts in the fund's investments over the past six months and one year, and performance information.
Investments	<Click Here>	A complete list of the fund's investments.
Financial Statements	<Click Here>	Statements of assets and liabilities, operations, and changes in net assets, as well as financial highlights.
Notes	<Click Here>	Notes to the financial statements.
Report of Independent Registered Public Accounting Firm	<Click Here>
Trustees and Officers	<Click Here>
Distributions	<Click Here>
Board Approval of Investment Advisory Contracts and Management Fees	<Click Here>

To view a fund's proxy voting guidelines and proxy voting record for the 12-month period ended June 30, visit http://www.fidelity.com/proxyvotingresults or visit the Securities and Exchange Commission's (SEC) web site at http://www.sec.gov. You may also call 1-800-544-8544 to request a free copy of the proxy voting guidelines.

Standard & Poor's, S&P and S&P 500 are registered service marks of The McGraw-Hill Companies, Inc. and have been licensed for use by Fidelity Distributors Corporation.

Other third party marks appearing herein are the property of their respective owners.

All other marks appearing herein are registered or unregistered trademarks or service marks of FMR LLC or an affiliated company.

The fund seeks to obtain as high a level of current income as is consistent with the preservation of capital and liquidity by investing in high-quality, short-term money market securities.

Annual Report

Investments in the fund are neither insured nor guaranteed by the U.S. Government, and there can be no assurance that the fund will maintain a stable $1.00 share price.

This report and the financial statements contained herein are submitted for the general information of the shareholders of the fund. This report is not authorized for distribution to prospective investors in the fund unless preceded or accompanied by an effective prospectus.

A fund files its complete schedule of portfolio holdings with the SEC for the first and third quarters of each fiscal year on Form N-Q. Forms N-Q are available on the SEC's web site at http://www.sec.gov. A fund's Forms N-Q may be reviewed and copied at the SEC's Public Reference Room in Washington, DC. Information regarding the operation of the SEC's Public Reference Room may be obtained by calling 1-800-SEC-0330. For a complete list of a fund's portfolio holdings, view the most recent holdings listing, semiannual report, or annual report on Fidelity's web site at http://www.fidelity.com or http://www.advisor.fidelity.com, as applicable.

NOT FDIC INSURED · MAY LOSE VALUE · NO BANK GUARANTEE

Neither the fund nor Fidelity Distributors Corporation is a bank.

Annual Report

Shareholder Expense Example

As a shareholder of the Fund, you incur two types of costs: (1) transaction costs, and (2) ongoing costs, including management fees and other Fund expenses. This Example is 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 Example is based on an investment of $1,000 invested at the beginning of the period and held for the entire period (March 1, 2009 to August 31, 2009).

Actual Expenses

The first line of the accompanying table provides information about actual account values and actual expenses. You may use the information in this line, together with the amount you invested, to estimate the expenses that you paid over the period. Simply divide your account value by $1,000.00 (for example, an $8,600 account value divided by $1,000.00 = 8.6), then multiply the result by the number in the first line 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 line of the accompanying table provides information about hypothetical account values and hypothetical expenses based on the Fund's actual expense ratio and an assumed rate of return of 5% per year before expenses, which is not the Fund's 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 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 transaction costs. Therefore, the second line of the table is useful in comparing ongoing costs only, and will not help you determine the relative total costs of owning different funds.

	Annualized Expense Ratio	Beginning Account Value March 1, 2009	Ending Account Value August 31, 2009	Expenses Paid During Period* March 1, 2009 to August 31, 2009
Actual	.45%	$ 1,000.00	$ 1,003.40	$ 2.27
Hypothetical (5% return per year before expenses)		$ 1,000.00	$ 1,022.94	$ 2.29

* Expenses are equal to the Fund's annualized expense ratio, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period).

Annual Report

Investment Changes/Performance (Unaudited)

Maturity Diversification
Days	% of fund's investments 8/31/09	% of fund's investments 2/28/09	% of fund's investments 8/31/08
0 - 30	30.8	31.6	52.5
31 - 90	46.7	48.2	31.9
91 - 180	14.0	11.8	11.3
181 - 397	8.5	8.4	4.3
Weighted Average Maturity
	8/31/09	2/28/09	8/31/08
Retirement Money Market Portfolio	69 Days	68 Days	50 Days
All Taxable Money Market Funds Average*	52 Days	49 Days	44 Days

Asset Allocation (% of fund's net assets)
As of August 31, 2009		As of February 28, 2009
	Corporate Bonds 1.2%		Corporate Bonds 0.1%
	Commercial Paper 15.0%		Commercial Paper 12.0%
	Bank CDs, BAs, TDs, and Notes 60.1%		Bank CDs, BAs, TDs, and Notes 60.0%
	Government Securities† 20.9%		Government Securities† 22.2%
	Repurchase Agreements 3.4%		Repurchase Agreements 8.3%
	Other Investments 0.2%		Other Investments 0.0%
	Net Other Assets** (0.8)%		Net Other Assets** (2.6)%

**Net Other Assets are not included in the pie chart.

^† Includes FDIC Guaranteed Corporate Securities

Current and Historical Seven Day Yields

	9/1/09	6/2/09	3/3/09	12/2/08	9/2/08
Retirement Money Market Portfolio	0.32%	0.68%	1.03%	2.43%	2.48%

Yield refers to the income paid by the fund over a given period. Yields for money market funds are usually for seven-day periods, as they are here, though they are expressed as annual percentage rates. Past performance is no guarantee of future results. Yield will vary and it is possible to lose money by investing in the fund.

*Source: iMoneyNet, Inc.

Annual Report

Investments August 31, 2009

Showing Percentage of Net Assets

Corporate Bonds - 1.2%
	Due Date	Yield (a)	Principal Amount (000s)	Value (000s)
LP Pinewood SPV LLC
	9/8/09	0.40% (d)	$ 25,000	$ 25,000
Roche Holdings, Inc.
	9/18/09	1.95 (f)	193,250	193,250
TOTAL CORPORATE BONDS				218,250
Certificates of Deposit - 49.6%
London Branch, Eurodollar, Foreign Banks - 16.5%
Bayerische Hypo-und Vereinsbank AG
	10/27/09	0.50	63,000	63,000
Calyon SA
	11/9/09	1.10	45,000	45,000
Commonwealth Bank of Australia
	11/18/09	0.65	30,000	30,001
Credit Agricole SA
	10/22/09 to 5/20/10	0.60 to 1.10	549,000	549,000
Credit Industriel et Commercial
	9/3/09 to 10/19/09	0.35 to 0.74	314,000	314,000
Danske Bank AS
	10/6/09	0.40	131,000	131,001
HSBC Bank PLC
	10/30/09 to 11/27/09	0.50 to 1.00	75,000	75,000
ING Bank NV
	10/6/09 to 12/14/09	0.40 to 0.58	336,000	336,000
Landesbank Baden-Wuert
	9/14/09 to 9/21/09	0.37	345,000	345,002
Landesbank Hessen-Thuringen
	9/2/09 to 1/4/10	0.63 to 0.70	407,000	407,000
National Australia Bank Ltd.
	9/29/09 to 11/5/09	0.40 to 1.05	355,000	355,000
UniCredit SpA
	9/8/09 to 10/13/09	0.60 to 0.71	323,000	323,000
				2,973,004
Certificates of Deposit - continued
	Due Date	Yield (a)	Principal Amount (000s)	Value (000s)
New York Branch, Yankee Dollar, Foreign Banks - 33.1%
Bank of Montreal
	10/7/09	0.34%	$ 48,000	$ 48,000
Bank of Nova Scotia
	9/8/09 to 11/23/09	0.51 to 1.00 (d)	577,000	577,000
Bank Tokyo-Mitsubishi UFJ Ltd.
	11/9/09 to 1/25/10	0.40 to 0.51	537,000	537,000
BNP Paribas SA
	10/16/09 to 4/20/10	0.59 to 1.18	532,000	532,000
Calyon New York Branch Institutional Certificates Prog. Bill of Exchange
	9/8/09	0.78 (d)	140,000	140,000
Canadian Imperial Bank of Commerce
	10/16/09	0.31	254,000	254,000
Commerzbank AG
	10/8/09 to 11/2/09	0.50 to 0.60	379,000	379,000
Deutsche Bank AG
	10/5/09	0.81 (d)	315,000	315,000
Fortis Banque SA
	9/30/09 to 10/23/09	0.40 to 0.70	115,000	115,000
Intesa Sanpaolo SpA
	12/17/09 to 1/6/10	0.59 to 0.61	133,000	133,000
Natexis Banques Populaires NY
	11/19/09	0.93 (d)	37,000	37,000
Natixis New York Branch
	9/22/09	0.66 (d)	88,000	88,000
Natixis SA
	9/1/09 to 11/10/09	0.50 to 1.10 (d)	242,000	242,000
Rabobank Nederland
	9/9/09 to 5/18/10	0.52 to 1.20	801,000	801,141
Royal Bank of Canada
	9/9/09 to 1/12/10	0.90 to 1.20 (d)	205,000	205,000
Royal Bank of Scotland PLC
	10/15/09 to 11/19/09	0.43 to 0.50	621,000	621,000
Societe Generale
	10/27/09 to 11/5/09	0.37 to 1.03 (d)	188,000	188,000
Sumitomo Mitsui Banking Corp.
	10/15/09	0.40	43,000	43,000
Certificates of Deposit - continued
	Due Date	Yield (a)	Principal Amount (000s)	Value (000s)
New York Branch, Yankee Dollar, Foreign Banks - continued
Toronto-Dominion Bank
	9/10/09 to 4/16/10	0.50 to 1.90% (d)	$ 615,000	$ 615,000
UBS AG
	11/25/09	0.44	112,000	112,000
				5,982,141
TOTAL CERTIFICATES OF DEPOSIT				8,955,145
Commercial Paper - 15.0%
Banco Bilbao Vizcaya Argentaria SA (London Branch)
	11/23/09	0.40	32,000	31,970
Caisse Nationale des Caisses d' Epargne et de Prevoyance
	10/2/09 to 11/19/09	0.45 to 0.75	25,000	24,975
Comcast Corp.
	9/21/09	0.86 (b)	98,000	97,953
Commerzbank U.S. Finance, Inc.
	11/20/09	0.50	100,000	99,889
CVS Caremark Corp.
	9/3/09 to 11/4/09	0.62 to 1.10	69,000	68,951
Dakota Notes (Citibank Credit Card Issuance Trust)
	9/8/09 to 10/22/09	0.53 to 0.65	360,000	359,810
DnB NOR Bank ASA
	9/17/09	0.59	28,000	27,993
Emerald Notes (BA Credit Card Trust)
	9/1/09 to 10/26/09	0.95 to 1.20	192,000	191,805
General Electric Co.
	9/23/09	0.26	54,000	53,991
Groupe Bpce
	11/2/09 to 12/8/09	0.48 to 0.51	196,000	195,792
HVB U.S. Finance, Inc.
	10/2/09 to 10/9/09	0.55	68,000	67,965
Intesa Funding LLC
	9/8/09 to 1/15/10	0.62 to 1.00	111,000	110,919
Irish Republic
	10/22/09	0.55	111,000	110,914
Commercial Paper - continued
	Due Date	Yield (a)	Principal Amount (000s)	Value (000s)
Landesbank Hessen-Thuringen
	10/7/09	0.58%	$ 28,000	$ 27,984
Natexis Banques Populaires U.S. Finance Co. LLC
	9/15/09 to 11/2/09	0.65 to 0.71	153,000	152,872
Nationwide Building Society
	9/3/09 to 10/30/09	0.51 to 0.70	261,000	260,868
Palisades Notes (Citibank Omni Master Trust)
	9/1/09 to 9/3/09	0.90	146,000	145,996
Pfizer, Inc.
	4/20/10 to 4/30/10	0.60 to 0.65	72,000	71,705
Sanpaolo IMI U.S. Financial Co.
	11/23/09	0.58	12,000	11,984
Societe Generale North America, Inc.
	9/15/09	0.27	55,000	54,994
Time Warner Cable, Inc.
	9/14/09 to 9/16/09	0.47	88,000	87,984
Toronto Dominion Holdings (USA)
	10/5/09 to 3/8/10	0.55 to 1.65	182,000	181,705
UniCredito Italiano Bank (Ireland) PLC
	9/21/09	0.60	45,000	44,985
Vodafone Group PLC
	9/1/09	0.88	50,000	50,000
Westpac Banking Corp.
	9/11/09 to 5/11/10	0.63 to 0.70 (d)	171,000	170,730
TOTAL COMMERCIAL PAPER				2,704,734
U.S. Government and Government Agency Obligations - 2.6%
Other Government Related - 2.6%
Bank of America NA (FDIC Guaranteed)
	9/14/09 to 10/29/09	0.55 to 0.66 (c)(d)	269,414	269,414
Citibank NA (FDIC Guaranteed)
	9/30/09	0.65 (c)(d)	44,000	44,000
General Electric Capital Corp. (FDIC Guaranteed)
	10/8/09	0.60 (c)(d)	158,035	158,035
TOTAL U.S. GOVERNMENT AND GOVERNMENT AGENCY OBLIGATIONS				471,449
Federal Agencies - 14.7%
	Due Date	Yield (a)	Principal Amount (000s)	Value (000s)
Fannie Mae - 4.2%
	9/25/09 to 2/22/10	0.61 to 3.37%	$ 756,000	$ 754,201
Federal Home Loan Bank - 6.6%
	9/19/09 to 8/17/10	0.23 to 1.69 (d)	1,180,900	1,181,337
Freddie Mac - 3.9%
	9/3/09 to 11/3/09	0.62 to 0.86 (d)	710,000	709,545
TOTAL FEDERAL AGENCIES				2,645,083
U.S. Treasury Obligations - 3.6%
U.S. Treasury Bills - 3.6%
	12/17/09 to 8/26/10	0.35 to 0.73	660,773	658,372
Medium-Term Notes - 9.9%
AT&T, Inc.
	10/2/09	1.05 (b)(d)	152,000	152,000
Bank of America NA
	10/5/09	0.80 (d)	165,000	165,000
Bank of Montreal
	9/8/09	0.80 (b)(d)	50,000	50,000
Banque Federative du Credit Mutuel
	11/28/09	0.72 (b)(d)	96,000	96,000
BP Capital Markets PLC
	9/11/09	0.77 (d)	65,000	65,000
Cellco Partnership
	12/27/09	1.11 (b)(d)	74,000	74,000
Commonwealth Bank of Australia
	10/6/09	0.80 (b)(d)	135,000	135,000
General Electric Capital Corp.
	10/5/09	0.61 (d)	7,000	7,001
Metropolitan Life Global Funding I
	12/7/09	1.20 (b)(d)	29,000	29,000
National Australia Bank Ltd.
	9/8/09	0.86 (b)(d)	85,000	85,000
New York Life Insurance Co.
	9/30/09 to 11/30/09	1.41 to 1.75 (d)(f)	109,000	109,000
Medium-Term Notes - continued
	Due Date	Yield (a)	Principal Amount (000s)	Value (000s)
Nordea Bank AB
	10/23/09	0.87% (d)	$ 325,000	$ 325,000
Procter & Gamble Co.
	9/9/09	0.66 (d)	37,000	37,000
Procter & Gamble International Funding SCA
	11/7/09	0.48 (d)	34,000	34,000
Royal Bank of Canada
	9/15/09 to 11/16/09	0.69 to 0.78 (b)(d)	170,000	170,000
Verizon Communications, Inc.
	9/15/09	0.93 (d)	105,000	105,000
Westpac Banking Corp.
	9/4/09	0.89 (b)(d)	147,000	146,999
TOTAL MEDIUM-TERM NOTES				1,785,000
Short-Term Notes - 0.4%
Metropolitan Life Insurance Co.
	9/1/09 to 10/1/09	0.93 to 2.10 (d)(f)	65,000	65,000
Time Deposits - 0.2%
Banco Santander SA
	9/22/09 to 9/25/09	0.50	45,000	45,000
Asset-Backed Securities - 0.2%
Harley-Davidson Motorcycle Trust
	7/15/10	0.72	30,021	30,021

Repurchase Agreements - 3.4%
	Maturity Amount (000s)
In a joint trading account at 0.22% dated 8/31/09 due 9/1/09 (Collateralized by U.S. Government Obligations) #	$ 716		716
With:
Barclays Capital, Inc. at:
0.48%, dated 8/31/09 due 9/1/09 (Collateralized by Commercial Paper Obligations valued at $74,160,989, 9/8/09 - 1/4/10)	72,001		72,000
Repurchase Agreements - continued
	Maturity Amount (000s)		Value (000s)
With: - continued
Barclays Capital, Inc. at:
0.5%, dated:
8/14/09 due 9/14/09 (Collateralized by Equity Securities valued at $46,211,551)	$ 42,018		$ 42,000
8/21/09 due 11/19/09 (Collateralized by Corporate Obligations valued at $6,301,076, 6.85%, 5/25/16)	6,008		6,000
Deutsche Bank Securities, Inc. at:
0.25%, dated 8/18/09 due 9/16/09 (Collateralized by Commercial Paper Obligations valued at $17,562,302, 9/15/09 - 11/16/09)	17,003		17,000
0.27%, dated 8/25/09 due 9/25/09 (Collateralized by Commercial Paper Obligations valued at $34,042,531, 9/25/09)	33,008		33,000
0.35%, dated 8/25/09 due 11/25/09 (Collateralized by Commercial Paper Obligations valued at $24,884,807, 9/25/09)	24,021		24,000
0.38%, dated:
8/17/09 due 11/13/09 (Collateralized by Commercial Paper Obligations valued at $32,103,645, 11/13/09)	31,029		31,000
8/18/09 due 11/16/09 (Collateralized by Commercial Paper Obligations valued at $17,644,094, 9/16/09)	17,016		17,000
0.48%, dated 8/31/09 due 9/1/09 (Collateralized by Equity Securities valued at $170,502,274)	155,002		155,000
0.55%, dated 7/1/09 due 10/1/09 (Collateralized by Commercial Paper Obligations valued at $15,571,084, 10/1/09)	15,021		15,000
Merrill Lynch, Pierce, Fenner & Smith at 0.48%, dated 8/24/09 due 11/24/09 (Collateralized by Equity Securities valued at $61,606,259) (d)(e)	56,069		56,000
Morgan Stanley & Co. at 0.42%, dated 8/20/09 due 11/18/09 (Collateralized by Equity Securities valued at $92,412,942)	84,088		84,000
RBC Capital Markets Co. at 0.53%, dated 8/31/09 due 9/1/09 (Collateralized by Equity Securities valued at $9,900,185)	9,000		9,000
UBS Securities LLC at 0.55%, dated 7/2/09 due 9/29/09 (Collateralized by Corporate Obligations valued at $54,650,594, 5.25% - 7.7%, 1/15/11 - 11/15/33)	52,071		52,000
TOTAL REPURCHASE AGREEMENTS		613,716
TOTAL INVESTMENT PORTFOLIO - 100.8% (Cost $18,191,770)			18,191,770
NET OTHER ASSETS - (0.8)%			(144,595)
NET ASSETS - 100%		$ 18,047,175

Legend

(a) Yield represents either the annualized yield at the date of purchase, or the stated coupon rate, or, for floating rate securities, the rate at period end.

(b) Security exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be resold in transactions exempt from registration, normally to qualified institutional buyers. At the end of the period, the value of these securities amounted to $1,035,952,000 or 5.7% of net assets.

(c) Under the Temporary Liquidity Guarantee Program, the Federal Deposit Insurance Corporation guarantees principal and interest in the event of payment default or bankruptcy until the earlier of maturity date of the debt or until June 30, 2012. At the end of the period these securities amounted to $471,449,000 or 2.6% of net assets.

(d) Coupon rates for floating and adjustable rate securities reflect the rates in effect at period end. Due dates for these security types are the next interest rate reset date or, when applicable, the final maturity date.

(e) The maturity amount is based on the rate at period end.

(f) Restricted securities - Investment in securities not registered under the Securities Act of 1933 (excluding 144A issues). At the end of the period, the value of restricted securities (excluding 144A issues) amounted to $367,250,000 or 2.0% of net assets.

Additional information on each holding is as follows:

Security	Acquisition Date	Cost (000s)
Metropolitan Life Insurance Co.: 0.93%, 9/1/09	2/24/03	$ 20,000
2.1%, 10/1/09	3/26/02	$ 45,000
New York Life Insurance Co.: 1.41%, 11/30/09	5/8/09	$ 42,000
1.75%, 9/30/09	3/23/09	$ 67,000
Roche Holdings, Inc. 1.95%, 9/18/09	3/13/09	$ 193,250

# Additional information on each counterparty to the repurchase agreement is as follows:

Repurchase Agreement / Counterparty	Value (Amounts in thousands)
$716,000 due 9/01/09 at 0.22%
BNP Paribas Securities Corp.	$ 55
Banc of America Securities LLC	62
Bank of America, NA	95
Barclays Capital, Inc.	77
Citigroup Global Markets, Inc.	48
Credit Suisse Securities (USA) LLC	32
Deutsche Bank Securities, Inc.	52
Greenwich Capital Markets, Inc.	16
ING Financial Markets LLC	33
J.P. Morgan Securities, Inc.	103
Merrill Lynch Government Securities, Inc.	8
Mizuho Securities USA, Inc.	42
RBC Capital Markets Corp.	4
Societe Generale, New York Branch	32
UBS Securities LLC	49
Wachovia Capital Markets LLC	8
	$ 716

Other Information

All investments are categorized as Level 2 under the Fair Value Hierarchy. The inputs or methodology used for valuing securities may not be an indication of the risk associated with investing in those securities. For more information on valuation inputs, please refer to the Security Valuation section in the accompanying Notes to Financial Statements.

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements

Statement of Assets and Liabilities

Amounts in thousands (except per-share amount)	August 31, 2009
Assets
Investment in securities, at value (including repurchase agreements of $613,716) - See accompanying schedule: Unaffiliated issuers (cost $18,191,770)		$ 18,191,770
Receivable for fund shares sold		45,758
Interest receivable		26,442
Prepaid expenses		317
Other receivables		228
Total assets		18,264,515
Liabilities
Payable for investments purchased	$ 161,015
Payable for fund shares redeemed	49,732
Distributions payable	10
Accrued management fee	6,352
Other affiliated payables	2
Other payables and accrued expenses	229
Total liabilities		217,340
Net Assets		$ 18,047,175
Net Assets consist of:
Paid in capital		$ 18,045,008
Accumulated undistributed net realized gain (loss) on investments		2,167
Net Assets, for 18,043,591 shares outstanding		$ 18,047,175
Net Asset Value, offering price and redemption price per share ($18,047,175 ÷ 18,043,591 shares)		$ 1.00

See accompanying notes which are an integral part of the financial statements.

Annual Report

Statement of Operations

Amounts in thousands	Year ended August 31, 2009
Investment Income
Interest		$ 344,489
Expenses
Management fee	$ 76,870
Independent trustees' compensation	66
Money Market Guarantee Program Fee	6,308
Total expenses before reductions	83,244
Expense reductions	(117)	83,127
Net investment income		261,362
Realized and Unrealized Gain (Loss) Net realized gain (loss) on:
Investment securities:
Unaffiliated issuers		3,741
Net increase in net assets resulting from operations		$ 265,103

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements - continued

Statement of Changes in Net Assets

Amounts in thousands	Year ended August 31, 2009	Year ended August 31, 2008
Increase (Decrease) in Net Assets
Operations
Net investment income	$ 261,362	$ 594,614
Net realized gain (loss)	3,741	881
Net increase in net assets resulting from operations	265,103	595,495
Distributions to shareholders from net investment income	(261,370)	(594,610)
Share transactions at net asset value of $1.00 per share Proceeds from sales of shares	13,450,269	13,607,747
Reinvestment of distributions	261,277	594,383
Cost of shares redeemed	(11,958,023)	(13,970,219)
Net increase (decrease) in net assets and shares resulting from share transactions	1,753,523	231,911
Total increase (decrease) in net assets	1,757,256	232,796
Net Assets
Beginning of period	16,289,919	16,057,123
End of period	$ 18,047,175	$ 16,289,919

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Highlights

Years ended August 31,	2009	2008	2007	2006	2005
Selected Per-Share Data
Net asset value, beginning of period	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Income from Investment Operations
Net investment income	.015	.037	.050	.042	.022
Distributions from net investment income	(.015)	(.037)	(.050)	(.042)	(.022)
Net asset value, end of period	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Total ReturnA	1.46%	3.72%	5.15%	4.32%	2.23%
Ratios to Average Net Assets B
Expenses before reductions	.45%	.42%	.42%	.42%	.42%
Expenses net of fee waivers, if any	.45%	.42%	.42%	.42%	.42%
Expenses net of all reductions	.45%	.40%	.39%	.40%	.41%
Net investment income	1.43%	3.66%	5.03%	4.24%	2.21%
Supplemental Data
Net assets, end of period (in millions)	$ 18,047	$ 16,290	$ 16,057	$ 16,609	$ 16,164

^A Total returns would have been lower had certain expenses not been reduced during the periods shown.

^B Expense ratios reflect operating expenses of the Fund. Expenses before reductions do not reflect amounts reimbursed by the investment adviser or expense offset arrangements and do not represent the amount paid by the Fund during periods when reimbursements or reductions occur. Expenses net of fee waivers reflect expenses after reimbursement by the investment adviser but prior to reductions from expense offset arrangements. Expenses net of all reductions represent the net expenses paid by the Fund.

See accompanying notes which are an integral part of the financial statements.

Annual Report

Notes to Financial Statements

For the period ended August 31, 2009

(Amounts in thousands except ratios)

1. Organization.

Retirement Money Market Portfolio (the Fund) is a fund of Fidelity Money Market Trust (the trust) and is authorized to issue an unlimited number of shares. The trust is registered under the Investment Company Act of 1940, as amended (the 1940 Act), as an open-end management investment company organized as a Delaware statutory trust.

2. Significant Accounting Policies.

The financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America, which require management to make certain estimates and assumptions at the date of the financial statements. Actual results could differ from those estimates. Events or transactions occurring after period end through the date that the financial statements were issued, October 13, 2009, have been evaluated in the preparation of the financial statements. The following summarizes the significant accounting policies of the Fund:

Security Valuation. As permitted by compliance with certain conditions under Rule 2a-7 of the 1940 Act, securities are valued at amortized cost, which approximates value. Generally Accepted Accounting Principles (GAAP) establishes a disclosure hierarchy that categorizes the inputs to valuation techniques used to value assets and liabilities at measurement date. These inputs are classified into three levels. Level 1 includes readily available unadjusted quoted prices in active markets for identical assets or liabilities. Level 2 includes observable inputs other than quoted prices included in Level 1 that are observable either directly or indirectly. Level 3 includes unobservable inputs when market prices are not readily available or reliable.

Investment Transactions and Income. The net asset value per share for processing shareholder transactions is calculated as of the close of business of the New York Stock Exchange (NYSE), normally 4:00 p.m. Eastern time. Security transactions are accounted for as of trade date. Gains and losses on securities sold are determined on the basis of identified cost. Interest income is accrued as earned. Interest income includes coupon interest and amortization of premium and accretion of discount on debt securities.

Expenses. Most expenses of the trust can be directly attributed to a fund. Expenses which cannot be directly attributed are apportioned among each Fund in the trust. Expense estimates are accrued in the period to which they relate and adjustments are made when actual amounts are known.

The Board of Trustees of the Fund approved the participation by the Fund in the U.S. Treasury Department's Temporary Guarantee Program for Money Market Funds (the "Program") through September 18, 2009. Under the Program, if the Fund's market value per share drops below $0.995 on any day while the Program is in effect, shareholders of record on that date who also held shares in the Fund on September 19, 2008 may be

Annual Report

2. Significant Accounting Policies - continued

Expenses - continued

eligible to receive a payment from the U.S. Treasury Department upon liquidation of the Fund. The Fund paid the U.S. Treasury Department fees equal to 0.04% based on the number of shares outstanding as of September 19, 2008 to participate in the Program. The fees are being amortized over the length of the participation in the Program. The expense is borne by the Fund without regard to any expense limitation currently in effect for the Fund.

Deferred Trustee Compensation. Under a Deferred Compensation Plan (the Plan), independent Trustees must defer receipt of a portion of, and may elect to defer receipt of an additional portion of, their annual compensation. Deferred amounts are invested in a cross-section of Fidelity funds, are marked-to-market and remain in the Fund until distributed in accordance with the Plan. The investment of deferred amounts and the offsetting payable to the Trustees are included in the accompanying Statement of Assets and Liabilities.

Income Tax Information and Distributions to Shareholders. Each year, the Fund intends to qualify as a regulated investment company by distributing substantially all of its taxable income and realized gains under Subchapter M of the Internal Revenue Code and filing its U.S. federal tax return. As a result, no provision for income taxes is required. The Fund is subject to the provisions of FASB Interpretation No. 48, Accounting for Uncertainties in Income Taxes (FIN 48). FIN 48 sets forth a minimum threshold for financial statement recognition of the benefit of a tax position taken or expected to be taken in a tax return. There are no unrecognized tax benefits in the accompanying financial statements. A Fund's federal tax return is subject to examination by the Internal Revenue Service (IRS) for a period of three years.

Dividends are declared daily and paid monthly from net investment income. Distributions from realized gains, if any, are recorded on the ex-dividend date. Income and capital gain distributions are determined in accordance with income tax regulations, which may differ from generally accepted accounting principles. In addition, the Fund will claim a portion of the payment made to redeeming shareholders as a distribution for income tax purposes.

Capital accounts within the financial statements are adjusted for permanent book-tax differences. These adjustments have no impact on net assets or the results of operations. Temporary book-tax differences will reverse in a subsequent period.

Book-tax differences are primarily due to deferred trustees compensation and excise tax regulations.

Annual Report

Notes to Financial Statements - continued

(Amounts in thousands except ratios)

2. Significant Accounting Policies - continued

Income Tax Information and Distributions to Shareholders - continued

The tax-basis components of distributable earnings and the federal tax cost as of period end were as follows:

Unrealized appreciation	$ -
Unrealized depreciation	-
Net unrealized appreciation (depreciation)	$ -
Undistributed ordinary income	$ 2,397
Cost for federal income tax purposes	$ 18,191,770

The tax character of distributions paid was as follows:

	August 31, 2009	August 31, 2008
Ordinary Income	$ 261,370	$ 594,610

3. Operating Policies.

Repurchase Agreements. Fidelity Management & Research Company (FMR) has received an Exemptive Order from the Securities and Exchange Commission (the SEC) which permits the Fund and other affiliated entities of FMR to transfer uninvested cash balances into joint trading accounts which are then invested in repurchase agreements. The Fund may also invest directly with institutions in repurchase agreements. Repurchase agreements are collateralized by government or non-government securities. Upon settlement date, collateral is held in segregated accounts with custodian banks and may be obtained in the event of a default of the counterparty. The Fund monitors, on a daily basis, the value of the collateral to ensure it is at least equal to the principal amount of the repurchase agreement (including accrued interest). In the event of a default by the counterparty, realization of the collateral proceeds could be delayed, during which time the value of the collateral may decline.

Restricted Securities. The Fund may invest in securities that are subject to legal or contractual restrictions on resale. These securities generally may be resold in transactions exempt from registration or to the public if the securities are registered. Disposal of these securities may involve time-consuming negotiations and expense, and prompt sale at an acceptable price may be difficult. Information regarding restricted securities is included at the end of the Fund's Schedule of Investments.

Annual Report

4. Fees and Other Transactions with Affiliates.

Management Fee. FMR and its affiliates provide the Fund with investment management related services for which the Fund pays a monthly management fee that is based on an annual rate of .42% of the Fund's average net assets. FMR pays all other expenses, except the compensation of the independent Trustees and certain exceptions such as interest expense. The management fee paid to FMR by the Fund is reduced by an amount equal to the fees and expenses paid by the Fund to the independent Trustees.

5. Expense Reductions.

Through arrangements with the Fund's custodian and transfer agent, credits realized as a result of uninvested cash balances were used to reduce the Fund's management fee. During the period, these credits reduced the Fund's management fee by $117.

6. Other.

The Fund's organizational documents provide former and current 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.

Annual Report

Report of Independent Registered Public Accounting Firm

To the Trustees of Fidelity Money Market Trust and the Shareholders of Retirement Money Market Portfolio:

In our opinion, the accompanying statement of assets and liabilities, including the schedule of investments, and the related statements of operations and of changes in net assets and the financial highlights present fairly, in all material respects, the financial position of Retirement Money Market Portfolio (a fund of Fidelity Money Market Trust) at August 31, 2009, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period then ended and the financial highlights for each of the five years in the period then ended, in conformity with accounting principles generally accepted in the United States of America. These financial statements and financial highlights (hereafter referred to as "financial statements") are the responsibility of the Retirement Money Market Portfolio's management. Our responsibility is to express an opinion on these financial statements based on our audits. We conducted our audits of these financial statements 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 are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits, which included confirmation of securities at August 31, 2009 by correspondence with the custodian and brokers, provide a reasonable basis for our opinion.

/s/ PricewaterhouseCoopers LLP

PricewaterhouseCoopers LLP

Boston, Massachusetts

October 13, 2009

Annual Report

Trustees and Officers

The Trustees and executive officers of the trust and fund, as applicable, are listed below. The Board of Trustees governs the fund and is responsible for protecting the interests of shareholders. The Trustees are experienced executives who meet periodically throughout the year to oversee the fund's activities, review contractual arrangements with companies that provide services to the fund, and review the fund's performance. Except for James C. Curvey, each of the Trustees oversees 187 funds advised by FMR or an affiliate. Mr. Curvey oversees 407 funds advised by FMR or an affiliate.

The Trustees hold office without limit in time except that (a) any Trustee may resign; (b) any Trustee may be removed by written instrument, signed by at least two-thirds of the number of Trustees prior to such removal; (c) any Trustee who requests to be retired or who has become incapacitated by illness or injury may be retired by written instrument signed by a majority of the other Trustees; and (d) any Trustee may be removed at any special meeting of shareholders by a two-thirds vote of the outstanding voting securities of the trust. Each Trustee who is not an interested person (as defined in the 1940 Act) (Independent Trustee), shall retire not later than the last day of the calendar year in which his or her 72nd birthday occurs. The Independent Trustees may waive this mandatory retirement age policy with respect to individual Trustees. The executive officers hold office without limit in time, except that any officer may resign or may be removed by a vote of a majority of the Trustees at any regular meeting or any special meeting of the Trustees. Except as indicated, each individual has held the office shown or other offices in the same company for the past five years.

Interested Trustees*:

The fund's Statement of Additional Information (SAI) includes more information about the Trustees. To request a free copy, call Fidelity at 1-800-544-8544.

Correspondence intended for each Trustee who is an interested person may be sent to Fidelity Investments, 82 Devonshire Street, Boston, Massachusetts 02109.

Name, Age; Principal Occupation
Abigail P. Johnson (47)
	Year of Election or Appointment: 2009 Ms. Johnson is Trustee and Chairman of the Board of Trustees of certain Trusts. Ms. Johnson serves as President of Personal and Workplace Investing (2005-present). Ms. Johnson is a Director of FMR LLC. Previously, Ms. Johnson served as President and a Director of FMR (2001-2005), a Trustee of other investment companies advised by FMR, Fidelity Investments Money Management, Inc., and FMR Co., Inc. (2001-2005), Senior Vice President of the Fidelity funds (2001-2005), and managed a number of Fidelity funds. Ms. Abigail P. Johnson and Mr. Arthur E. Johnson are not related.
James C. Curvey (74)
	Year of Election or Appointment: 2007 Mr. Curvey also serves as Trustee (2007-present) of other investment companies advised by FMR. Mr. Curvey is a Director of FMR and FMR Co., Inc. (2007-present). Mr. Curvey is also Vice Chairman (2006- present) and Director of FMR LLC. In addition, Mr. Curvey serves as an Overseer for the Boston Symphony Orchestra and a member of the Trustees of Villanova University.

* Trustees have been determined to be "Interested Trustees" by virtue of, among other things, their affiliation with the trust or various entities under common control with FMR.

Independent Trustees:

Correspondence intended for each Independent Trustee (that is, the Trustees other than the Interested Trustees) may be sent to Fidelity Investments, P.O. Box 55235, Boston, Massachusetts 02205-5235.

Name, Age; Principal Occupation
Albert R. Gamper, Jr. (67)
	Year of Election or Appointment: 2006 Prior to his retirement in December 2004, Mr. Gamper served as Chairman of the Board of CIT Group Inc. (commercial finance). During his tenure with CIT Group Inc. Mr. Gamper served in numerous senior management positions, including Chairman (1987-1989; 1999-2001; 2002-2004), Chief Executive Officer (1987-2004), and President. Mr. Gamper currently serves as a member of the Board of Directors of Public Service Enterprise Group (utilities), a member of the Board of Trustees, Rutgers University (2004-present), and Chairman of the Board of Saint Barnabas Health Care System. Previously, Mr. Gamper served as Chairman of the Board of Governors, Rutgers University (2004-2007).
Arthur E. Johnson (62)
	Year of Election or Appointment: 2008 Mr. Johnson serves as a member of the Board of Directors of Eaton Corporation (diversified power management, 2009-present) and AGL Resources, Inc. (holding company). Previously, Mr. Johnson served as Senior Vice President of Corporate Strategic Development of Lockheed Martin Corporation (defense contractor, 1999-2009), and on the Board of Directors of IKON Office Solutions, Inc. (1999-2008). Mr. Arthur E. Johnson and Ms. Abigail P. Johnson are not related.
Michael E. Kenneally (55)
	Year of Election or Appointment: 2009 Mr. Kenneally also serves as Trustee (2009-present) or Member of the Advisory Board (2008-present) of other Fidelity Fixed Income and Asset Allocation Funds. Previously, Mr. Kenneally served as Chairman and Global Chief Executive Officer of Credit Suisse Asset Management (2003-2005). Mr. Kenneally was a Director of The Credit Suisse Funds (U.S. Mutual Fund, 2004-2008) and was awarded the Chartered Financial Analyst (CFA) designation in 1991.
James H. Keyes (68)
	Year of Election or Appointment: 2007 Mr. Keyes serves as a member of the Boards of Navistar International Corporation (manufacture and sale of trucks, buses, and diesel engines) and Pitney Bowes, Inc. (integrated mail, messaging, and document management solutions). Previously, Mr. Keyes served as a member of the Board of LSI Logic Corporation (semiconductor technologies, 1984-2008).
Marie L. Knowles (62)
	Year of Election or Appointment: 2001 Prior to Ms. Knowles' retirement in June 2000, she served as Executive Vice President and Chief Financial Officer of Atlantic Richfield Company (ARCO) (diversified energy, 1996-2000). From 1993 to 1996, she was a Senior Vice President of ARCO and President of ARCO Transportation Company. She served as a Director of ARCO from 1996 to 1998. Ms. Knowles currently serves as a Director of McKesson Corporation (healthcare service). Ms. Knowles is an Honorary Trustee of the Brookings Institution and a member of the Board of the Catalina Island Conservancy and of the Santa Catalina Island Company (2009-present). She also serves as a member of the Advisory Board for the School of Engineering of the University of Southern California and the Foundation Board of the School of Architecture at the University of Virginia (2007-present). Previously, Ms. Knowles served as a Director of Phelps Dodge Corporation (copper mining and manufacturing, 1994-2007).
Kenneth L. Wolfe (70)
	Year of Election or Appointment: 2005 Mr. Wolfe served as Chairman and a Director (2007-2009) and Chairman and Chief Executive Officer of Hershey Foods Corporation, and as a member of the Boards of Adelphia Communications Corporation (telecommunications, 2003-2006), Bausch & Lomb, Inc. (medical/pharmaceutical, 1993-2007), and Revlon, Inc. (2004-2009).

Annual Report

Executive Officers:

Correspondence intended for each executive officer may be sent to Fidelity Investments, 82 Devonshire Street, Boston, Massachusetts 02109.

Name, Age; Principal Occupation
John R. Hebble (51)
	Year of Election or Appointment: 2008 President and Treasurer of Fidelity's Fixed Income and Asset Allocation Funds. Mr. Hebble also serves as Assistant Treasurer of other Fidelity funds (2009-present) and is an employee of Fidelity Investments.
Boyce I. Greer (53)
	Year of Election or Appointment: 2005 or 2006 Vice President of Fidelity's Fixed Income Funds (2006) and Asset Allocation Funds (2005). Mr. Greer is also a Trustee of other investment companies advised by FMR. Mr. Greer is President of the Asset Allocation Division (2008-present), President and a Director of Strategic Advisers, Inc. (2008-present), President and a Director of Fidelity Investments Money Management, Inc. (2007-present), and an Executive Vice President of FMR and FMR Co., Inc. (2005-present). Previously, Mr. Greer served as a Director and Managing Director of Strategic Advisers, Inc. (2002-2005).
Charles S. Morrison (48)
	Year of Election or Appointment: 2005 Vice President of Fidelity's Money Market Funds. Mr. Morrison also serves as President, Money Market Group Leader of FMR (2009-present), and as Executive Vice President of Fidelity Management & Research (U.K.) Inc. (2008-present). Previously, Mr. Morrison served as Senior Vice President, Money Market Group of FMR (2004-2009), Vice President of Fidelity's Bond Funds and certain Balanced, and Asset Allocation Funds.
Scott C. Goebel (41)
	Year of Election or Appointment: 2008 Secretary and Chief Legal Officer (CLO) of the Fidelity funds. Mr. Goebel also serves as General Counsel, Secretary, and Senior Vice President of FMR (2008-present) and FMR Co., Inc. (2008-present); Deputy General Counsel of FMR LLC; Chief Legal Officer of Fidelity Management & Research (Hong Kong) Limited (2008-present) and Assistant Secretary of Fidelity Management & Research (Japan) Inc. (2008-present), Fidelity Investments Money Management, Inc. (2008-present), Fidelity Management & Research (U.K.) Inc. (2008-present), and Fidelity Research and Analysis Company (2008-present). Previously, Mr. Goebel served as Assistant Secretary of the Funds (2007-2008) and as Vice President and Secretary of Fidelity Distributors Corporation (FDC) (2005-2007).
Holly C. Laurent (55)
	Year of Election or Appointment: 2008 Anti-Money Laundering (AML) Officer of the Fidelity funds. Ms. Laurent is an employee of Fidelity Investments. Previously, Ms. Laurent was Senior Vice President and Head of Legal for Fidelity Business Services India Pvt. Ltd. (2006-2008), and Senior Vice President, Deputy General Counsel and Group Head for FMR LLC (2005-2006).
Christine Reynolds (50)
	Year of Election or Appointment: 2008 Chief Financial Officer of the Fidelity funds. Ms. Reynolds became President of Fidelity Pricing and Cash Management Services (FPCMS) in August 2008. Ms. Reynolds served as Chief Operating Officer of FPCMS (2007-2008). Previously, Ms. Reynolds served as President, Treasurer, and Anti-Money Laundering officer of the Fidelity funds (2004-2007).
Michael H. Whitaker (42)
	Year of Election or Appointment: 2008 Chief Compliance Officer of Fidelity's Fixed Income and Asset Allocation Funds. Mr. Whitaker is an employee of Fidelity Investments (2007-present). Prior to joining Fidelity Investments, Mr. Whitaker worked at MFS Investment Management where he served as Senior Vice President and Chief Compliance Officer (2004-2006), and Assistant General Counsel.
Jeffrey S. Christian (47)
	Year of Election or Appointment: 2009 Deputy Treasurer of the Fidelity funds. Mr. Christian also serves as Chief Financial Officer of other Fidelity funds (2008-present) and is an employee of Fidelity Investments. Previously, Mr. Christian served as Senior Vice President of Fidelity Pricing and Cash Management Services (FPCMS) (2004-2009) and as Vice President of Business Analysis (2003-2004).
Bryan A. Mehrmann (48)
	Year of Election or Appointment: 2005 Deputy Treasurer of the Fidelity funds. Mr. Mehrmann is an employee of Fidelity Investments. Previously, Mr. Mehrmann served as Vice President of Fidelity Investments Institutional Services Group (FIIS)/Fidelity Investments Institutional Operations Company, Inc. (FIIOC) Client Services (1998-2004).
Stephanie J. Dorsey (40)
	Year of Election or Appointment: 2008 Deputy Treasurer of Fidelity's Fixed Income and Asset Allocation Funds. Ms. Dorsey is an employee of Fidelity Investments (2008-present). Previously, Ms. Dorsey served as Treasurer (2004-2008) of the JPMorgan Mutual Funds and Vice President (2004-2008) of JPMorgan Chase Bank.
Paul M. Murphy (62)
	Year of Election or Appointment: 2007 Assistant Treasurer of the Fidelity funds. Mr. Murphy is an employee of Fidelity Investments. Previously, Mr. Murphy served as Chief Financial Officer of the Fidelity funds (2005-2006), Vice President and Associate General Counsel of FMR (2007), and Senior Vice President of Fidelity Pricing and Cash Management Services (FPCMS) (1994-2007).
Kenneth B. Robins (40)
	Year of Election or Appointment: 2009 Assistant Treasurer of the Fidelity Fixed Income and Asset Allocation Funds. Mr. Robins also serves as President and Treasurer of other Fidelity funds and is an employee of Fidelity Investments (2004-present). Before joining Fidelity Investments, Mr. Robins worked at KPMG LLP, where he was a partner in KPMG's department of professional practice (2002-2004).
Gary W. Ryan (51)
	Year of Election or Appointment: 2005 Assistant Treasurer of the Fidelity funds. Mr. Ryan is an employee of Fidelity Investments. Previously, Mr. Ryan served as Vice President of Fund Reporting in Fidelity Pricing and Cash Management Services (FPCMS) (1999-2005).

Annual Report

Distributions (Unaudited)

A total of 6.86% of the dividends distributed during the fiscal year was derived from interest on U.S. Government securities which is generally exempt from state income tax.

The fund designates $95,421,514 of distributions paid during the period January 1, 2009 to August 31, 2009 as qualifying to be taxed as interest-related dividends for nonresident alien shareholders.

The fund will notify shareholders in January 2010 of amounts for use in preparing 2009 income tax returns.

Annual Report

Board Approval of Investment Advisory Contracts and Management Fees

Fidelity Retirement Money Market Portfolio

On May 21, 2009, the Board of Trustees, including the Independent Trustees (together, the Board), voted to continue the management contract and subadvisory agreements (together, the Advisory Contracts) for the fund for four months, through September 30, 2009, in connection with the reorganization of the Board's new meeting schedule. The Board considered that the contractual terms of and fees payable under the fund's Advisory Contracts involve no changes in (i) the investment process or strategies employed in the management of the fund's assets; (ii) the nature or level of services provided under the fund's Advisory Contracts; or (iii) the day-to-day management of the fund or the persons primarily responsible for such management. The Board concluded that the fund's Advisory Contracts are fair and reasonable, and that the fund's Advisory Contracts should be renewed, without modification, through September 30, 2009, with the understanding that the Board will consider their renewal in September 2009.

Annual Report

Investment Adviser

Fidelity Management &
Research Company
Boston, MA

Investment Sub-Advisers

Fidelity Investments Money
Management, Inc.

Fidelity Management & Research
(U.K.) Inc.

Fidelity Management & Research
(Hong Kong) Limited

Fidelity Management & Research
(Japan) Inc.

FIL Investment Advisors

FIL Investment Advisors
(U.K.) Ltd.

Fidelity Research & Analysis Company

General Distributor

Fidelity Distributors Corporation

Boston, MA

Transfer and Service Agents

Fidelity Investments Institutional
Operations Company, Inc.
Boston, MA

Fidelity Service Company, Inc.
Boston, MA

Custodian

JPMorgan Chase Bank

New York, NY

RMM-ANN-1009
1.768778.107

Item 2. Code of Ethics

As of the end of the period, August 31, 2009, Fidelity Money Market Trust (the trust) has adopted a code of ethics, as defined in Item 2 of Form N-CSR, that applies to its President and Treasurer and its Chief Financial Officer. A copy of the code of ethics is filed as an exhibit to this Form N-CSR.

Item 3. Audit Committee Financial Expert

The Board of Trustees of the trust has determined that Marie L. Knowles is an audit committee financial expert, as defined in Item 3 of Form N-CSR.   Ms. Knowles is independent for purposes of Item 3 of Form N-CSR.  

Item 4. Principal Accountant Fees and Services

Fees and Services

The following table presents fees billed by PricewaterhouseCoopers LLP ("PwC") in each of the last two fiscal years for services rendered to Retirement Government Money Market Portfolio and Retirement Money Market Portfolio (the "Funds"):

Services Billed by PwC

August 31, 2009 Fees^A

	Audit Fees	Audit-Related Fees	Tax Fees	All Other Fees
Retirement Government Money Market Portfolio	$58,000	$-	$2,000	$5,400
Retirement Money Market Portfolio	$88,000	$-	$2,000	$15,400

August 31, 2008 Fees^A

	Audit Fees	Audit-Related Fees	Tax Fees	All Other Fees
Retirement Government Money Market Portfolio	$53,000	$-	$2,000	$3,300
Retirement Money Market Portfolio	$73,000	$-	$2,000	$9,000

^A Amounts may reflect rounding.

The following table presents fees billed by PwC that were required to be approved by the Audit Committee for services that relate directly to the operations and financial reporting of the Funds and that are rendered on behalf of Fidelity Management & Research Company ("FMR") and entities controlling, controlled by, or under common control with FMR (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser) that provide ongoing services to the Funds ("Fund Service Providers"):

Services Billed by PwC

	August 31, 2009A	August 31, 2008A
Audit-Related Fees	$3,015,000	$1,480,000B
Tax Fees	$2,000	$-
All Other Fees	$-	$- B

^A Amounts may reflect rounding.

^B Reflects current period presentation.

"Audit-Related Fees" represent fees billed for assurance and related services that are reasonably related to the performance of the fund audit or the review of the fund's financial statements and that are not reported under Audit Fees.

"Tax Fees" represent fees billed for tax compliance, tax advice or tax planning that relate directly to the operations and financial reporting of the fund.

"All Other Fees" represent fees billed for assurance services provided to the fund or Fund Service Provider that relate directly to the operations and financial reporting of the fund, excluding those services that are reported under Audit Fees, Audit-Related Fees or Tax Fees.

Assurance services must be performed by an independent public accountant.

* * *

The aggregate non-audit fees billed by PwC for services rendered to the Funds, FMR (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser), and any Fund Service Provider for each of the last two fiscal years of the Funds are as follows:

Billed By	August 31, 2009 A	August 31, 2008 A
PwC	$3,895,000	$2,470,000

^A Amounts may reflect rounding.

The trust's Audit Committee has considered non-audit services that were not pre-approved that were provided by PwC to Fund Service Providers to be compatible with maintaining the independence of PwC in its audit of the Funds, taking into account representations from PwC, in accordance with Public Company Accounting Oversight Board rules, regarding its independence from the Funds and their related entities and FMR's review of the appropriateness and permissibility under applicable law of such non-audit services prior to their provision to the Fund Service Providers.

Audit Committee Pre-Approval Policies and Procedures

The trust's Audit Committee must pre-approve all audit and non-audit services provided by a fund's independent registered public accounting firm relating to the operations or financial reporting of the fund. Prior to the commencement of any audit or non-audit services to a fund, the Audit Committee reviews the services to determine whether they are appropriate and permissible under applicable law.

The Audit Committee has adopted policies and procedures to, among other purposes, provide a framework for the Committee's consideration of non-audit services by the audit firms that audit the Fidelity funds. The policies and procedures require that any non-audit service provided by a fund audit firm to a Fidelity fund and any non-audit service provided by a fund auditor to a Fund Service Provider that relates directly to the operations and financial reporting of a Fidelity fund ("Covered Service") are subject to approval by the Audit Committee before such service is provided.

All Covered Services must be approved in advance of provision of the service either: (i) by formal resolution of the Audit Committee, or (ii) by oral or written approval of the service by the Chair of the Audit Committee (or if the Chair is unavailable, such other member of the Audit Committee as may be designated by the Chair to act in the Chair's absence). The approval contemplated by (ii) above is permitted where the Treasurer determines that action on such an engagement is necessary before the next meeting of the Audit Committee.

Non-audit services provided by a fund audit firm to a Fund Service Provider that do not relate directly to the operations and financial reporting of a Fidelity fund are reported to the Audit Committee on a periodic basis.

Non-Audit Services Approved Pursuant to Rule 2-01(c)(7)(i)(C) and (ii) of Regulation S-X ("De Minimis Exception")

There were no non-audit services approved or required to be approved by the Audit Committee pursuant to the De Minimis Exception during the Funds' last two fiscal years relating to services provided to (i) the Funds or (ii) any Fund Service Provider that relate directly to the operations and financial reporting of the Funds.

Item 5. Audit Committee of Listed Registrants

Not applicable.

Item 6. Investments

(a) Not applicable.

(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. Purchase 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

There were no material changes to the procedures by which shareholders may recommend nominees to the trust's Board of Trustees.

Item 11. Controls and Procedures

(a)(i) The President and Treasurer and the Chief Financial Officer have concluded that the trust's disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act) provide reasonable assurances that material information relating to the trust is made known to them by the appropriate persons, based on their evaluation of these controls and procedures as of a date within 90 days of the filing date of this report.

(a)(ii) There was no change in the trust's internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act) that occurred during the second fiscal quarter of the period covered by this report that has materially affected, or is reasonably likely to materially affect, the trust's internal control over financial reporting.

Item 12. Exhibits

(a)	(1)	Code of Ethics pursuant to Item 2 of Form N-CSR is filed and attached hereto as EX-99.CODE ETH.
(a)	(2)	Certification pursuant to Rule 30a-2(a) under the Investment Company Act of 1940 (17 CFR 270.30a-2(a)) is filed and attached hereto as Exhibit 99.CERT.
(a)	(3)	Not applicable.
(b)		Certification pursuant to Rule 30a-2(b) under the Investment Company Act of 1940 (17 CFR 270.30a-2(b)) is furnished and attached hereto as Exhibit 99.906CERT.

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.

Fidelity Money Market Trust

By:	/s/John R. Hebble
	John R. Hebble
	President and Treasurer
Date:	October 28, 2009

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/John R. Hebble
	John R. Hebble
	President and Treasurer
Date:	October 28, 2009

By:	/s/Christine Reynolds
	Christine Reynolds
	Chief Financial Officer
Date:	October 28, 2009