EXHIBIT 32.1

      CERTIFICATION OF PERIODIC FINANCIAL REPORT BY CHIEF EXECUTIVE OFFICER
            PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Form 10-Q for the quarterly period ended June 30, 2003 of
First Financial Bancorp. (the "Company"), as filed with the Securities and
Exchange Commission on August 8, 2003 (the "Report"), I, Stanley N. Pontius,
President and Chief Executive Officer of the Company, certify, 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/ Stanley N. Pontius
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Stanley N. Pontius
President and Chief Executive Officer

August 8, 2003