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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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                                    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): JANUARY 11, 2006

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                           MERCANTILE BANK CORPORATION
             (Exact name of registrant as specified in its charter)

<TABLE>
<S>                            <C>                        <C>
          MICHIGAN                     000-26719                38-3360865
(State or other jurisdiction   (Commission File Number)        (IRS Employer
      of incorporation)                                   Identification Number)
</TABLE>

<TABLE>
<S>                                                             <C>
310 LEONARD STREET NW, GRAND RAPIDS, MICHIGAN                      49504
   (Address of principal executive offices)                     (Zip Code)
</TABLE>

         Registrant's telephone number, including area code 616-406-3000

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):

[ ]  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))

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ITEM 2.02 RESULTS OF OPERATIONS AND FINANCIAL CONDITION.

     Earnings Release. On January 11, 2006, Mercantile Bank Corporation issued a
press release announcing earnings and other financial results for the quarter
and year ended December 31, 2005. A copy of the press release is furnished as
Exhibit 99.1 to this report and incorporated here by reference.

     In accordance with General Instruction B.2 of Form 8-K, the information in
this Current Report on Form 8-K, including Exhibit 99.1, shall not be deemed to
be "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as
amended (the "Exchange Act"), or otherwise subject to the liability of that
section, and shall not be incorporated by reference into any registration
statement or other document filed under the Securities Act of 1933, as amended,
or the Exchange Act, except as shall be expressly set forth by specific
reference in such filing.

ITEM 9.01 FINANCIAL STATEMENTS AND EXHIBITS.

(d) Exhibits.

<TABLE>
<CAPTION>
Exhibit Number                            Description
--------------                            -----------
<S>              <C>
     99.1        Press release of Mercantile Bank Corporation reporting
                 financial results and earnings for the quarter and year ended
                 December 31, 2005.
</TABLE>


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                                   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 hereunto duly authorized.

                                        MERCANTILE BANK CORPORATION


                                        By: /s/ Charles E. Christmas
                                            ------------------------------------
                                            Charles E. Christmas
                                            Senior Vice President,
                                            Chief Financial Officer and
                                            Treasurer

Date: January 11, 2006


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                                  EXHIBIT INDEX

<TABLE>
<CAPTION>
Exhibit Number                            Description
--------------                            -----------
<S>              <C>
     99.1        Press release of Mercantile Bank Corporation reporting
                 financial results and earnings for the quarter and year ended
                 December 31, 2005.
</TABLE>


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