EXHIBIT 32.1



SARBANES-OXLEY ACT OF 2002, SECTION 906 CERTIFICATION BY CHIEF EXECUTIVE
OFFICER

As an accompaniment to the Annual Report of MainSource Financial Group, Inc.
(the "Company") on Form 10-K for the period ending December 31, 2004 as filed
with the Securities and Exchange Commission on the date hereof (the "Report"),
I, James L. Saner Sr., 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 to my knowledge:

o    The Report fully complies with the requirements of section 13(a) or 15(d)
     of the Securities Exchange Act of 1934, and
o    The information contained in the Report fairly presents, in all material
     respects, the financial condition and results of operations of the Company
     as of and for the periods presented.

This certification is based on inquiries that I have made, or have caused to be
made, in a good faith effort on my part to be a responsible and competent chief
executive officer serving the Company and its many constituencies.

This certification merely accompanies and is not part of the Report, shall not
be deemed filed for purposes of the Securities Exchange Act of 1934, and may not
be used for any purpose other than compliance with 18 U.S.C. Section 1350, as
adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.


/s/  James L. Saner, Sr.
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