Federated Municipal Securities Fund, Inc.

Summary PROSPECTUS

May 31, 2010

CLASS A SHARES (TICKER LMSFX)
CLASS B SHARES (TICKER LMSBX)
CLASS C SHARES (TICKER LMSCX)
CLASS F SHARES (TICKER LMFFX)

Before you invest, you may want to review the Fund's Prospectus, which contains more information about the Fund and its risks. You can find the Fund's Prospectus and other information about the Fund, including the Statement of Additional Information and most recent reports to shareholders, online at FederatedInvestors.com/prospectus. You can also get this information at no cost by calling 1-800-341-7400 or by sending an email request to services@federatedinvestors.com or from a financial intermediary through which Shares of the Fund may be bought or sold. The Fund's Prospectus and Statement of Additional Information, both dated May 31, 2010, are incorporated by reference into this Summary Prospectus.

A mutual fund seeking to provide for its shareholders a high level of current income which is exempt from federal regular income tax by investing at least a majority of its assets in a portfolio of: (1) long-term, tax-exempt securities; and (2) investment-grade, tax-exempt securities.

As with all mutual funds, the Securities and Exchange Commission (SEC) has not approved or disapproved these securities or passed upon the adequacy of this Prospectus. Any representation to the contrary is a criminal offense.

Fund Summary Information

RISK/RETURN SUMMARY: INVESTMENT OBJECTIVE

The Fund's investment objective is to provide for its shareholders a high level of current income which is exempt from federal regular income tax.

RISK/RETURN SUMMARY: FEES AND EXPENSES

This table describes the fees and expenses that you may pay if you buy and hold Class A Shares, Class B Shares, Class C Shares and Class F Shares of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000, or $1,000,000, in certain classes (e.g. Class A Shares and Class F Shares, respectively) of Federated funds. More information about these and other discounts is available from your financial professional and in the “What Do Shares Cost?” section of the Prospectus on page 24.

Shareholder Fees	Class A	Class B	Class C	Class F
Fees Paid Directly From Your Investment
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	4.50%	None	None	1.00%
Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, as applicable)	0.00%	5.50%	1.00%	1.00%
Maximum Sales Charge (Load) Imposed on Reinvested Dividends (and other Distributions) (as a percentage of offering price)	None	None	None	None
Redemption Fee (as a percentage of amount redeemed, if applicable)	None	None	None	None
Exchange Fee	None	None	None	None
Annual Fund Operating Expenses
Expenses That You Pay Each Year as a Percentage of the Value of Your Investment
Management Fee	0.53%	0.53%	0.53%	0.53%
Distribution (12b-1) Fee	None	0.75%	0.75%	None
Other Expenses	0.45%	0.45%	0.45%	0.45%
Total Annual Fund Operating Expenses	0.98%	1.73%	1.73%	0.98%
Fee Waivers and/or Expense Reimbursements1	0.11%	0.00%	0.00%	0.11%
Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements	0.87%	1.73%	1.73%	0.87%

1 The Adviser and its affiliates have voluntarily agreed to waive their fees and/or reimburse expenses so that the total annual fund operating expenses paid by the Fund's Class A Shares, Class B Shares, Class C Shares and Class F Shares (after the voluntary waivers and/or reimbursements) will not exceed 0.87%, 1.76%, 1.76% and 0.87% (the “Fee Limit”), respectively, through the later of (the “Termination Date”): (a) May 31, 2011; or (b) the date of the Fund's next effective Prospectus. While the Adviser and its affiliates currently do not anticipate terminating or increasing these arrangements prior to the Termination Date, these arrangements may only be terminated or the Fee Limit increased prior to the Termination Date with the agreement of the Fund's Board of Directors.

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Example

This Example is intended to help you compare the cost of investing in the Fund's Class A Shares, Class B Shares, Class C Shares and Class F Shares with the cost of investing in other mutual funds.

The Example assumes that you invest $10,000 in the Fund's Class A Shares, Class B Shares, Class C Shares and Class F Shares for the time periods indicated and then redeem all of your Shares at the end of those periods. Expenses assuming no redemption are also shown. The Example also assumes that your investment has a 5% return each year and that the Fund's Class A Shares, Class B Shares, Class C Shares and Class F Shares operating expenses are as shown in the table and remain the same. Although your actual costs and returns may be higher or lower, based on these assumptions your costs would be:

Share Class	1 Year	3 Years	5 Years	10 Years
Class A Shares:
Expenses assuming redemption	$545	$748	$967	$1,597
Expenses assuming no redemption	$545	$748	$967	$1,597
Class B Shares:
Expenses assuming redemption	$726	$945	$1,139	$1,842
Expenses assuming no redemption	$176	$545	$939	$1,842
Class C Shares:
Expenses assuming redemption	$276	$545	$939	$2,041
Expenses assuming no redemption	$176	$545	$939	$2,041
Class F Shares:
Expenses assuming redemption	$299	$509	$636	$1,289
Expenses assuming no redemption	$199	$409	$636	$1,289

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 23% of the average value of its portfolio.

RISK/RETURN SUMMARY: INVESTMENTS, RISKS, PERFORMANCE

What are the Fund's Main Investment Strategies?

The Fund pursues its objective by investing its assets so that, normally (except as discussed herein), distributions of annual interest income are exempt from federal regular income tax. The Fund's investment adviser (Adviser) also normally (except as discussed herein) will invest the Fund's assets entirely in securities whose interest is not subject to (or not a specific preference item for purposes of) the federal alternative minimum tax for individuals and corporations (AMT), such that, normally, distributions of annual interest income also are exempt from

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the AMT. However, in certain circumstances (such as, for example, when there is a lack of supply of non-AMT securities, there are advantageous market conditions, or if there are changes in the tax laws relating to AMT), to pursue the Fund's investment objective, the Adviser may invest the Fund's assets in securities that may be subject to AMT. When there is a lack of supply of non-AMT securities and/or other circumstances that exist, such circumstances may result in the Fund acquiring AMT securities that are consistent with the Fund's investment objective. These acquisitions may occur in the ordinary course or in connection with fund reorganization transactions (i.e., transactions in which the Fund acquires the portfolio securities of other mutual funds), an issuer bankruptcy or another event or circumstance. In such circumstances, interest from the Fund's investments may be subject to the AMT.

The Fund does not limit itself to securities of a particular maturity range. Currently, the Fund invests at least a majority of its assets in long-term, tax-exempt securities (i.e., securities with stated maturities of 10 years or more).

The Fund also will invest at least a majority of its assets in securities rated investment grade (or unrated securities of comparable quality), and may purchase securities rated below investment grade (or unrated securities of comparable quality), which are also known as junk bonds, up to 49% of its assets. Investment-grade securities are securities that receive investment-grade ratings (i.e., generally ratings in the first, second, third or fourth highest rating category) by a nationally recognized statistical rating organization (NRSRO) or unrated securities of comparable quality. For example, securities rated “AAA,” “AA,” “A” or “BBB” by Standard & Poor's, an NRSRO, would be rated in the first, second, third or fourth ratings category, respectively. Securities rated below investment grade (or noninvestment-grade securities) are securities that do not receive investment-grade ratings (i.e., generally ratings below one of the four highest rating categories) by an NRSRO or unrated securities of comparable quality. For example, securities rated “B” or “BB” by Standard & Poor's, an NRSRO, would be noninvestment-grade securities. The Fund does not have a specific minimum quality rating.

The tax-exempt securities in which the Fund may principally invest include general obligation bonds, special revenue bonds, private activity bonds, tax increment financing bonds, municipal leases, zero-coupon securities, inverse floaters, municipal mortgage-backed securities, planned amortization classes, variable rate demand instruments, municipal notes and municipal auction rate securities. Certain of the tax-exempt securities in which the Fund invests may be subject to credit enhancement. The Fund also may principally invest in derivative contracts (such as, for example, futures contracts, options contracts and swap contracts) and hybrid instruments to implement its investment strategies as more fully described herein.

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The Fund also may invest in certain securities as described herein (such as market discount bonds, credit default swaps and other derivative transactions) that will likely cause the Fund to realize a limited amount of ordinary income or short-term capital gains (which are treated as ordinary income for federal income tax purposes).

What are the Main Risks on Investing in the Fund?

All mutual funds take investment risks. Therefore, it is possible to lose money by investing in the Fund. The primary factors that may reduce the Fund's returns include:

• Interest Rate Risks. Prices of fixed-income securities (including tax-exempt securities) generally fall when interest rates rise. Interest rate changes have a greater effect on prices of fixed-income securities with longer durations.
• Credit Risks.There is a possibility that issuers of securities in which the Fund may invest may default in the payment of interest or principal on the securities when due, which would cause the Fund to lose money. Noninvestment-grade securities generally have a higher default risk than investment-grade securities.
• Liquidity Risks. Certain securities in which the Fund invests may be less readily marketable and may be subject to greater fluctuation in price than other securities. These features may make it more difficult to sell or buy a security at a favorable price or time. Noninvestment-grade securities generally have less liquidity than investment-grade securities. Liquidity risk also refers to the possibility that the Fund may not be able to close out a derivative contract when it wants to. Over-the-counter derivative contracts generally carry greater liquidity risk than exchange-traded contracts.
• Tax Risks. In order to pay interest except from federal income tax, tax-exempt securities must meet certain legal requirements. Failure to meet such requirements may cause the interest received and distributed by the Fund to shareholders to be taxable. The federal income tax treatment of payments in respect of certain derivative contracts is unclear. The Fund also may invest in market discount bonds, enter into credit default swap arrangements and other derivative transactions, and engage in other permissible activities that will likely cause the Fund to realize a limited amount of ordinary income or short-term capital gains (which are treated as ordinary income for federal income tax purposes). Consequently, for each of these reasons, the Fund may receive payments, and make distributions, that are treated as ordinary income for federal income tax purposes.
• Leverage Risks. Leverage risk is created when an investment, which includes, for example, an investment in a derivative contract, exposes the Fund to a level of risk that exceeds the amount invested. Changes in the value of such an investment magnify the Fund's risk of loss and potential for gain. Investments can have these same results if their returns are based on a multiple of a specified index, security or other benchmark.

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• Call Risks.The Fund's performance may be adversely affected by the possibility that an issuer of a security held by the Fund may redeem the security prior to maturity at a price below or above its current market value.
• Sector Risks. A substantial part of the Fund's portfolio may be comprised of securities issued or credit enhanced by companies in similar businesses, or with other similar characteristics. As a result, the Fund will be more susceptible to any economic, business, political or other developments which generally affect these entities.
• Prepayment Risks. When homeowners prepay their mortgages in response to lower interest rates, the Fund will be required to reinvest the proceeds at the lower interest rates available. Also, when interest rates fall, the price of municipal mortgage-backed securities may not rise to as great an extent as that of other fixed-income securities.
• Credit Enhancement Risk. The securities in which the Fund invests may be subject to credit enhancement (for example, guarantees, letters of credit or bond insurance). If the credit quality of the credit enhancement provider (for example, a bank or bond insurer) is downgraded, the rating on a security credit enhanced by such credit enhancement provider also may be downgraded. Having multiple securities credit enhanced by the same enhancement provider will increase the adverse effects on the Fund that are likely to result from a downgrading of, or a default by, such an enhancement provider. Adverse developments in the banking or bond insurance industries also may negatively affect the Fund.
• Risks Associated with Noninvestment-Grade Securities. The Fund may invest a portion of its assets in securities rated below investment grade (which are also known as junk bonds), which may be subject to greater economic, credit and liquidity risks than investment-grade securities.
• Risks Related to the Economy. Lower-grade bond returns are sensitive to changes in the economy. The value of the Fund's portfolio may decline in tandem with a drop in the overall value of the stock market based on negative developments in the U.S. and global economies.
• Risks of Investing in Derivative Contracts and Hybrid Instruments. Derivative contracts and hybrid instruments involve risks different from, or possibly greater than, risks associated with investing directly in securities and other traditional investments. Specific risk issues related to the use of such contracts and instruments include valuation and tax issues, increased potential for losses and/or costs to the Fund, and a potential reduction in gains to the Fund. Each of these issues is described in greater detail in this Prospectus. Derivative contracts and hybrid instruments may also involve other risks described in this Prospectus or the Fund's Statement of Additional Information (SAI), such as interest rate, credit, liquidity and leverage risks.

The Shares offered by this Prospectus are not deposits or obligations of any bank, are not endorsed or guaranteed by any bank and are not insured or guaranteed by the U.S. government, the Federal Deposit Insurance Corporation, the Federal Reserve Board or any other government agency.

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Performance: Bar Chart and Table

Risk/Return Bar Chart

The bar chart and performance table below reflect historical performance data for the Fund's Class A Shares. The performance information shown below will help you analyze the Fund's investment risks in light of its historical returns. The bar chart shows the variability of the Fund's Class A Shares total returns on a calendar year-by-year basis. The Average Annual Total Return table shows returns averaged over the stated periods, and includes comparative performance information. The Fund's performance will fluctuate, and past performance (before and after taxes) is not necessarily an indication of future results. Updated performance information for the Fund is available under the “Products” section at FederatedInvestors.com or by calling 1-800-341-7400.

The total returns shown in the bar chart do not reflect the payment of any sales charges or recurring shareholder account fees. If these charges or fees had been included, the returns shown would have been lower.

The Fund's Class A Shares total return for the three-month period from January 1, 2010 to March 31, 2010, was 1.16%.

Within the periods shown in the bar chart, the Fund's Class A Shares highest quarterly return was 7.91% (quarter ended September 30, 2009). Its lowest quarterly return was (4.58)% (quarter ended September 30, 2008).

Average Annual Total Return Table

In addition to Return Before Taxes, Return After Taxes is shown for the Fund's Class A Shares to illustrate the effect of federal taxes on Fund returns. After-tax returns are shown only for Class A Shares and after-tax returns for Class B Shares, Class C Shares and Class F Shares will differ from those shown below for Class A Shares. Actual after-tax returns depend on each investor's personal tax situation, and are likely to differ from those shown. After-tax returns are calculated using a standard set of assumptions. The stated returns assume the highest historical federal income and capital gains tax rates. These after-tax returns do not reflect the effect of any applicable state and local taxes. After-tax returns are not relevant to investors holding Shares through tax-deferred programs, such as IRA

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or 401(k) plans. Historical returns do not include the effect of a 1.00% front-end sales charge on Class C Shares purchased prior to February 1, 2007. Effective February 1, 2007, this sales charge was eliminated.

(For the Period Ended December 31, 2009)

	1 Year	5 Years	10 Years	Start of Performance
Class A Shares:
Return Before Taxes	8.41%	1.89%	4.22%
Return After Taxes on Distributions	8.41%	1.89%	4.22%
Return After Taxes on Distributions and Sale of Fund Shares	7.02%	2.23%	4.27%
Class B Shares:
Return Before Taxes	6.99%	1.59%	3.96%
Class C Shares:
Return Before Taxes	11.49%	1.94%	3.78%
Class F Shares(start of performance 5/31/2007):
Return Before Taxes	11.39%			1.42%
Barclays Capital Municipal Bond Index1(reflects no deduction for fees, expenses or taxes)	12.91%	4.32%	5.75%
Lipper General Municipal Debt Funds Average2	16.85%	2.88%	4.60%

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The Barclays Capital Municipal Bond Index is a broad market performance benchmark for the tax-exempt bond market. To be included in the Barclays Capital Municipal Bond Index, bonds must have a minimum credit rating of at least Baa3/BBB-, an outstanding par value of at least $7 million and be issued as part of a transaction of at least $75 million. The bonds must be fixed rate, have an issue date after December 31, 1990 and must be at least one year from their maturity date. Remarketed issues, taxable municipal bonds, bonds with floating rates and derivatives are excluded from the index.

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Lipper figures represent the average of the total returns reported by all of the mutual funds designated by Lipper, Inc. as falling into the respective categories indicated.

Fund Management

The Fund's Investment Adviser is Federated Investment Management Company.

J. Scott Albrecht, Senior Portfolio Manager, has been the Fund's portfolio manager since May 1996.

Purchase and Sale of Fund Shares

The minimum investment amount for the Fund's Class A Shares, Class B Shares, Class C Shares and Class F Shares is generally $1,500 for initial investments and $100 for subsequent investments. The minimum subsequent investment for Systematic Investment Programs is $50.

You may purchase, redeem or exchange Shares of the Fund on any day the New York Stock Exchange (NYSE) is open. Shares may be purchased through a financial intermediary or directly from the Fund, by wire or by check. Redeem or exchange through a financial intermediary or directly from the Fund by telephone at 1-800-341-7400 or by mail.

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TAX INFORMATION

It is anticipated that Fund distributions will be primarily dividends that are exempt from federal regular income tax, although a portion of the Fund's dividends may not be tax-exempt. Dividends may be subject to state and local taxes. Although the Fund does not seek to realize capital gains, the Fund may realize and distribute capital gains from time to time as a result of the Fund's normal investment activities. Any Fund distributions of capital gains are taxable at applicable capital gains rates. The Fund is generally not a suitable investment for retirement accounts.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund and/or its related companies may pay the intermediary for the sale of Fund Shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary's Web site for more information.

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Federated Municipal Securities Fund, Inc.
Federated Investors Funds
4000 Ericsson Drive
Warrendale, PA 15086-7561

Contact us at FederatedInvestors.com
or call 1-800-341-7400.

Federated Securities Corp., Distributor

Investment Company Act File No. 811-2677

Cusip 313913105
Cusip 313913204
Cusip 313913303
Cusip 313913402

Q450287 (5/10)

Federated is a registered mark of Federated Investors, Inc.
2010 Federated Investors, Inc.