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FEDERATED MUNICIPAL SECURITIES FUND, INC.
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CLASS A SHARES
CLASS B SHARES
CLASS C SHARES
CLASS F SHARES
SUPPLEMENT TO PROSPECTUS DATED MAY 31, 2007

1. Under the section entitled "What are the Specific Risks of Investing in the
Fund?" please delete the description for Tax Risks on page 19 of the Prospectus
in its entirety and replace with the following:


TAX RISKS
In order to pay interest that is exempt from federal regular 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.
   Changes or proposed changes in federal or state tax laws may cause the prices
of tax-exempt securities to fall and/or may affect the tax-exempt status of the
securities in which the Fund invests.
   Regarding the tax-exempt status of the securities in which the Fund invests,
shareholders of the Fund should note that the U.S. Supreme Court has recently
agreed to review a Kentucky state court decision (Kentucky v. Davis) that could
have important consequences for funds that invest in tax-exempt securities,
including the Fund. The Kentucky state court held as unconstitutional under the
Commerce Clause of the U.S. Constitution a Kentucky law that exempts interest
earned on Kentucky tax-exempt bonds from Kentucky's state income tax, but taxes
interest derived from non-Kentucky tax-exempt bonds. The U.S. Supreme Court
heard the case in November during its Fall, 2007, session and is likely to
render its decision in the spring or early summer of 2008. If the U.S. Supreme
Court affirms the Kentucky state court's ruling, the decision could affect the
tax status of the tax-exempt securities in which the Fund invests, and the
Fund's distributions, for state tax purposes. Such a decision would force State
legislators to decide whether to exempt all tax-exempt bonds from state income
tax or subject all such bonds to state income tax. The decision, and any change
in tax status, also may negatively affect the value of the municipal securities
in which the Fund invests. The Kentucky v. Davis case does not question or
challenge the tax status of tax-exempt bonds for purposes of the federal regular
income tax. If the U.S. Supreme Court affirms the Kentucky state court's ruling,
and the Adviser determines that the Fund may be negatively impacted in a
material respect, the Adviser will advise shareholders as it determines
necessary.
   The federal income tax treatment of payments in respect of certain derivative
contracts is unclear. Additionally, the Fund may not be able to close out
certain derivative contracts when it wants to. 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. Income from the Fund also may be subject to
AMT.



                                                               November 21, 2007

Cusip       313913105
Cusip       313913204
Cusip       313913303
Cusip       313913402

37654 (11/07)