FORM 10Q 2Q03 8/7/03 EXHIBIT 32.1

Published on August 7, 2003

EXHIBIT 32.1

CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report of Merrill Lynch & Co., Inc. (the
"Company") on Form 10-Q for the period ended June 27, 2003 as filed with the
Securities and Exchange Commission on the date hereof (the "Report"), I, E.
Stanley O'Neal, Chairman of the Board and Chief Executive Officer of the
Company, certify, pursuant to 18 U.S.C. section 1350, as adopted pursuant to
Section 906 of the Sarbanes-Oxley Act of 2002, that:

(1) The Report fully complies with the requirements of
Section 13(a) or 15(d) of the Securities Exchange Act of 1934;
and

(2) The information contained in the Report fairly presents, in
all material respects, the financial condition and results of
operations of the Company.


/s/ E. Stanley O'Neal
--------------------------------------------
E. Stanley O'Neal
Chairman of the Board and
Chief Executive Officer

Dated: August 7, 2003

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