SECTION 906 CERTIFICATION

Pursuant to 18 U.S.C.ss. 1350, the undersigned officers of Federated Municipal
Securities Income Trust on behalf of Federated California Municipal Income
Fund, Federated Michigan Intermediate Municipal Trust, Federated New York
Municipal Income Fund, Federated North Carolina Municipal Income Fund,
Federated Ohio Municipal Income Fund, Federated Pennsylvania Municipal Income
Fund, Federated Vermont Municipal Income Fund (the "Registrant"), hereby
certify, to the best of our knowledge, that the Registrant's Report on Form
N-CSR for the period ended August 31, 2005 (the "Report") fully complies with
the requirements of Section 13(a) or 15(d), as applicable, of the Securities
and Exchange Act of 1934 and that the information contained in the Report
fairly presents, in all material respects, the financial condition and
results of operations of the Registrant.


Dated: October 21, 2005

/s/ J. Christopher Donahue

Title: J. Christopher Donahue, President, Principal Executive Officer



Dated: October 21, 2005

/s/ Richard J. Thomas

Title: Richard J. Thomas, Treasurer, Principal Financial Officer

This certification is being furnished solely pursuant to 18 U.S.C.ss. 1350 and
is not being filed as part of the Report or as a separate disclosure document.