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): May 25, 2006

                        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. Employer
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:

     [ ] 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 May 25, 2006,  MainSource  Financial Group,  Inc. issued a press release
     announcing the  consummation,  effective May 24, 2006 at 11:59 p.m., of the
     acquisition of HFS Bank, F.S.B. by MainSource Bank - Hobart, a wholly owned
     subsidiary  of  MainSource  Financial  Group,  Inc.  With  total  assets of
     approximately $236 million,  HFS Bank operates 6 offices in Porter and Lake
     Counties,  Indiana.  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 May 25, 2006.

                                   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:    May 25, 2006               By:  /s/ James L. Saner, Sr.
                                         ---------------------------------------
                                         James L. Saner, Sr.
                                         President and Chief Executive Officer