First Midwest Bancorp (ONBPP) 8-K Financial statements and exhibits

Exhibit 99.1

Certification

Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, 18 U.S.C. Section 1350, the undersigned officer of First Midwest Bancorp, Inc. (the "Company"), hereby certifies that:

1. the Company's Quarterly Report on Form 10-Q for the quarter ended June 30, 2002 (the "Report") fully complies with the requirements of Section 13(a) or 15(d), as applicable, of the Securities and Exchange Act of 1934, as amended; 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/ROBERT P. O'MEARA

Name: Robert P. O'Meara
Title: Chief Executive Officer

Dated: August 13, 2002

The foregoing certification is being furnished solely pursuant to 18 U.S.C. Section 1350 and is not being filed as part of the Report or as a separate disclosure document.