UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 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 28, 2005

                        MainSource Financial Group, Inc.
             (Exact name of registrant as specified in its charter)

          Indiana                       0-12422              35-1562245
State or Other Jurisdiction of     Commission File No.     I.R.S. Emloyer
Incorporation or Organization                              Identification Number

                               201 North Broadway
                            Greensburg, Indiana 47240
                    (Address of principal executive offices)

                                 (812) 663-0157
                         (Registrant's Telephone Number,
                              Including Area Code)

                                       N/A
          (Former Name or Former Address, if Changed Since Last Report)

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:

[x] Written communications pursuant to Rule 425 under the Securities Act (17 CFR
230.425)
[ ] Soliciting  material pursuant to Rule 14a-12 under the Exchange Act
(17  CFR  240.14a-12)
[ ]  Pre-commencement  communications  pursuant  to  Rule 14d-2(b)  under the
Exchange  Act (17 CFR  240.14d-2(b))
[ ]  Pre-commencement communications  pursuant  to  Rule  13e-4(c)  under  the
Exchange  Act  (17 CFR 240.13e-4(c))



Item 7.01. Regulation FD Disclosure

On September 28, 2005, MainSource Financial Group, Inc. (the "Company"),  issued
a press release announcing that it had executed a definitive  agreement to merge
Peoples Ohio Financial  Corporation into MainSource  Financial  Group,  Inc. The
press  release is attached  hereto as an exhibit to this Current  Report on Form
8-K and is being  furnished  pursuant to this Item 7.01 as Exhibit  99.1 to this
Current Report on Form 8-K.

Item 9.01. Financial Statements and Exhibits

     (c) The  following  exhibit is  furnished  with this  report:

          Exhibit  No. Description

          99.1  MainSource   Financial  Group,  Inc.'s  press  release  dated
                September 28, 2005.

                                   SIGNATURES

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, thereunto duly authorized.

                                     MAINSOURCE FINANCIAL GROUP, INC.

Date:    September 28, 2005          By:  /s/ James L. Saner, Sr.
                                          -----------------------------------
                                          James L. Saner, Sr.
                                          President and Chief Executive Officer