EXHIBIT (99.1) CEO CERTIFICATION OF PERIODIC REPORT

                        CERTIFICATION OF PERIODIC REPORT

I, Ralph W. Babb, Jr. of Comerica Incorporated (the "Company"), certify,
pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, 18 U.S.C. Section
1350, that:

(1)      The Amended Quarterly Report on Form 10-Q/A of the Company for the
         quarterly period ended June 30, 2002 (the "Report") fully complies with
         the requirements of Section 13(a) or 15(d) of the Securities Exchange
         Act of 1934 (15 U.S.C. 78m or 78o(d)); and

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

Dated: October 2, 2002

                                /s/ Ralph W. Babb, Jr.
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                                Ralph W. Babb, Jr.
                                Chairman, President and Chief Executive Officer