Item 5.02 Departure of Directors or Certain Officers; Election of Directors;
Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.
Resignation of Director. On March 17, 2009, our director, David M. Hecht, advised us that he is resigning from our Board of Directors, and that of our subsidiary, Mercantile Bank of Michigan, effective that day. Mr. Hecht has served as a member of our Board of Directors since 1997. Mr. Hecht's decision to resign is not a result of any disagreement with us relating to our operations, policies or practices.

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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: March 18, 2009