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We consent to the incorporation by reference of our report dated January 28,
2000, with respect to the consolidated financial statements and schedules of
Old Second Bancorp, Inc. incorporated by reference in its Annual Report (Form
10-K) for the year ended December 31, 1999, filed with the Securities and
Exchange Commission in the Registration Statement (Form S-8) pertaining to
the Old Second Bancorp, Inc. Employees 401(K) Savings Plan and Trust.
ERNST & YOUNG LLP
June 8, 2000
Chicago, Illinois
