UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of report (Date of earliest event reported):  September 22, 2016

MainSource Financial Group, Inc.

(Exact name of registrant as specified in its charter)

2105 N. State Road 3 Bypass

Greensburg, Indiana 47240

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code:  (812) 663-6734

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2 below):

o                                    Written communications pursuant to Rule 425 under the Securities Act (17 CFR 240.425)

o                                    Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o                                    Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o                                    Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01 Other Events.

On September 22, 2016, MainSource Financial Group, Inc. (the “Company”) made available on its website an Investor Presentation which provided information to investors about the Company, a copy of which is furnished herewith as Exhibit 99.1.  The Company may use the Investor Presentation in presentations to current and potential investors, lenders, creditors, insurers, vendors, customers, employees and others with an interest in the Company and its business. All information in Exhibit 99.1 is presented as of the particular date or dates referenced therein, and the Company does not undertake any obligation to, and disclaims any duty to, update any of the information provided.

The information in this Form 8-k, including Exhibit 99.1, shall not be deemed to be “filed” for purposes of Section 18 under the Securities Exchange Act of 1934 and shall not be deemed to be incorporated by reference into the Company’s filings under the Securities Act of 1933, except as specifically incorporated by reference therein.

Item 9.01.                                        Financial Statements and Exhibits.

(d)                                 Exhibits.

99.1                        Investor Presentation dated September 2016.

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date:  September 22, 2016

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EXHIBIT INDEX

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