SECTION 906 CERTIFICATION

Pursuant to 18 U.S.C.ss.  1350, the undersigned officers of Federated GNMA Trust
(the  "Registrant"),  hereby  certify,  to the best of our  knowledge,  that the
Registrant's  Report  on Form  N-CSR for the  period  ended  July 31,  2004 (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:  September 23, 2004
/s/ J. Christopher Donahue
Title: President, Principal Executive Officer



Dated:  September 23, 2004
/s/ Richard J. Thomas
Title: 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.