Form N-CSR Item 10(b) Exhibit
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CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

The undersigned hereby certify in their capacity as Treasurer and
President, respectively, of Eaton Vance Mutual Funds Trust (the "Trust")
(on behalf of Equity Research Fund), that:

(a) the Annual Report of the Trust (on behalf of Equity Research Fund)
on Form N-CSR for the period ended October 31, 2003 (the "Report") fully
complies with the requirements of Section 13(a) or 15(d) of the
Securities Exchange Act of 1934, as amended; and

(b) the information contained in the Report fairly presents, in all
material respects, the financial condition and the results of operations
of the Trust (on behalf of Equity Research Fund) for such period.

A signed original of this written statement required by section 906 has
been provided to the Trust and will be retained by the Trust and
furnished to the Securities and Exchange Commission or its staff upon
request.

Eaton Vance Mutual Funds Trust (On behalf of Equity Research Fund)

Date: December 19, 2003

/s/ James L. O'Connor
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James L. O'Connor
Treasurer

/s/ Thomas E. Faust Jr.
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Thomas E. Faust Jr.
President