EXHIBIT 99.1

Certification of Principal Executive Officer Pursuant to 31 CFR Section 30.15

I,
Archie M. Brown, Jr., Chief Executive Officer, certify, based on my knowledge, that:

(i)  The
Executive Compensation Committee of MainSource Financial Group, Inc. has discussed, reviewed, and evaluated with senior risk officers at least every six
months during any part of the most recently completed fiscal year that was a TARP period, the senior executive officer (SEO) compensation plans and the employee compensation plans and the risks these
plans pose to MainSource Financial Group, Inc.;

(ii)  The
Executive Compensation Committee of MainSource Financial Group, Inc. has identified and limited during any part of the most recently completed fiscal year
that was a TARP period any features of the SEO compensation plans that could lead SEOs to take unnecessary and excessive risks that could threaten the value of MainSource Financial Group, Inc.
and has identified any features of the employee compensation plans that pose risks to MainSource Financial Group, Inc. and has limited those features to ensure that MainSource Financial
Group, Inc. is not unnecessarily exposed to risks;

(iii)  The
Executive Compensation Committee has reviewed, at least every six months during any part of the most recently completed fiscal year that was a TARP period, the
terms of each employee compensation plan and identified any features of the plan that could encourage the manipulation of reported earnings of MainSource Financial Group, Inc. to enhance the
compensation of an employee, and has limited any such features;

(iv)  The
Executive Compensation Committee of MainSource Financial Group, Inc. will certify to the reviews of the SEO compensation plans and employee compensation
plans required under (i) and (iii) above;

(v)  The
Executive Compensation Committee of MainSource Financial Group, Inc. will provide a narrative description of how it limited during any part of the most
recently completed fiscal year that was a TARP period the features in:



(vi)  MainSource
Financial Group, Inc. has required that bonus payments to SEOs or any of the next twenty most highly compensated employees, as defined in the
regulations and guidance established under section 111 of EESA (bonus payments), be subject to a recovery or "clawback" provision during any part of the most recently completed fiscal year that
was a TARP period if the bonus payments were based on materially inaccurate financial statements or any other materially inaccurate performance metric criteria;

(vii)  MainSource
Financial Group, Inc. has prohibited any golden parachute payment, as defined in the regulations and guidance established under section 111 of
EESA, to an SEO or any of the next five most highly compensated employees during any part of the most recently completed fiscal year that was a TARP period;

(viii)  MainSource
Financial Group, Inc. has limited bonus payments to its applicable employees in accordance with section 111 of EESA and the regulations and
guidance established thereunder during any part of the most recently completed fiscal year that was a TARP period;

(ix)  MainSource
Financial Group, Inc. and its employees have complied with the excessive or luxury expenditures policy, as defined in the regulations and guidance
established under section 111 of EESA, during any part of the most recently completed fiscal year that was a TARP period; and any expenses that, pursuant to the policy, required approval of the
board of directors, a committee of the board of directors, an SEO, or an executive officer with a similar level of responsibility, were properly approved;

(x)  MainSource
Financial Group, Inc. will permit a non-binding shareholder resolution in compliance with any applicable federal securities rules and
regulations on the disclosures provided under the federal securities laws related to SEO compensation paid or accrued during any part of the most recently completed fiscal year that was a TARP period;

(xi)  MainSource
Financial Group, Inc. will disclose the amount, nature and justification for the offering, during any part of the most recently completed fiscal year
that was a TARP period, of any perquisites, as defined in the regulations and guidance established under section 111 of EESA, whose total value exceeds $25,000 for any employee who is subject
to the bonus payment limitations identified in paragraph (viii);

(xii)  MainSource
Financial Group, Inc . will disclose whether MainSource Financial Group, Inc., the board of directors of MainSource Financial Group, Inc, or the
Executive Compensation Committee of MainSource Financial Group, Inc. has engaged

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during
any part of the most recently completed fiscal year that was a TARP period a compensation consultant; and the services the compensation consultant or any affiliate of the compensation
consultant provided during this period;

(xiii)  MainSource
Financial Group, Inc. has prohibited the payment of any gross-ups, as defined in the regulations and guidance established under
section 111 of EESA, to the SEOs and the next twenty most highly compensated employees during any part of the most recently completed fiscal year that was a TARP period;

(xiv)  MainSource
Financial Group, Inc. has substantially complied with all other requirements related to employee compensation that are provided in the agreement
between MainSource Financial Group, Inc. and Treasury, including any amendments;

(xv)  MainSource
Financial Group, Inc. has submitted to Treasury a complete and accurate list of the SEOs and the twenty next most highly compensated employees for the
current fiscal year and the most recently completed fiscal year, with the non-SEOs ranked in descending order of level of annual compensation, and with name, title, and employer of each
SEO and most highly compensated employee identified; and

(xvi)  I
understand that a knowing and willful false or fraudulent statement made in connection with this certification may be punished by fine, imprisonment, or both. (See,
for example, 18 U.S.C. 1001)

Date:
March 10, 2011

By:    /s/
ARCHIE M. BROWN, JR.
          Archie M. Brown, Jr., Chief Executive Officer

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