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                                                             Exhibit 99.906 Cert

FORM N-CSR ITEM 11(b) EXHIBIT

                            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 SERIES TRUST (the "Trust") (on behalf
Eaton Vance Tax-Managed Growth Fund 1.0), that:

   (a)   the Semi-Annual Report of the Trust (on behalf of Eaton Vance
         Tax-Managed Growth Fund 1.0) on Form N-CSR for the period ended June
         30, 2004 (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 Eaton Vance Tax-Managed Growth
         Fund 1.0) 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 Series Trust (On behalf of Eaton Vance Tax-Managed Growth Fund 1.0)

Date: August 13, 2004
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/S/ Michelle A. Alexander
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Michelle A. Alexander
Treasurer

Date: August 13, 2004
      ---------------


/S/ Duncan W. Richardson
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Duncan W. Richardson
President