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                                                                    EXHIBIT 10.1

                           MERCANTILE BANK CORPORATION

                         2004 EMPLOYEE STOCK OPTION PLAN

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                      As adopted by the Board of Directors
                              on February 12, 2004

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ARTICLE I - PURPOSE

         The purpose of the 2004 Employee Stock Option Plan (the "Plan") of
Mercantile Bank Corporation (the "Company") is to enable officers and other
employees of the Company or any Subsidiary to participate in the Company's
future growth and profitability by offering them long-term performance-based
incentive compensation. The Plan also provides a means through which the Company
and its Subsidiaries can attract and retain key employees.

ARTICLE II - DEFINITIONS

         2.1 The following terms have the meaning described below when used in
the Plan:

         (a) "Board of Directors" shall mean the board of directors of the
Company.

         (b) "Code" shall mean the Internal Revenue Code of 1986, as amended,
and as it may be further amended from time to time.

         (c) "Common Stock" shall mean the Common Stock of the Company.

         (d) "Company" shall mean Mercantile Bank Corporation.

         (e) "Fair Market Value" on a particular date shall mean the average of
the highest and lowest sales prices of shares of the Common Stock reported on
The Nasdaq Stock Market (or any successor exchange or system that is the primary
exchange or system for trading of the Common Stock) on such date, or if The
Nasdaq Stock Market (or any such successor) is closed on that date, the last
preceding date on which The Nasdaq Stock Market (or any such successor) was open
for trading and on which shares of the Common Stock were traded. For purposes of
determining Fair Market Value, if there is only one sale of the Common Stock
reported on the applicable date, the sales price for such sale shall be used
instead, as though it were the average of the highest and lowest sales prices.
If for any reason it is not practical for the Fair Market Value to be determined
as provided for above in this paragraph, Fair Market Value shall be determined
by any fair and reasonable means prescribed by the Board of Directors.


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         (f) "Incentive Stock Option" shall mean a stock option granted under
Article VI that is intended to meet the requirements of Section 422 of the Code.

         (g) "Non-Qualified Stock Option" shall mean a stock option granted
under Article VI that is not intended to be an Incentive Stock Option.

         (h) "Option" shall mean an Incentive Stock Option or Non-Qualified
Stock Option.

         (i) "Participant" shall mean an eligible employee who has been granted
an Option.

         (j) "Subsidiary" shall mean with respect to an Incentive Stock Option
any "subsidiary corporation" (as such term is defined in Section 424(f) of the
Code or in any successor provision thereto), and as to a Nonqualified Stock
Option, Subsidiary shall mean any "subsidiary corporation", as described above,
or any other entity in which the Company, either directly or indirectly, owns a
majority voting interest.

ARTICLE III - ADMINISTRATION

         3.1 (a) Stock Option Plan Administration. The Board of Directors of the
Company shall administer the Plan. The Board of Directors shall have full power
and authority to grant to eligible employees (as determined by the Board of
Directors) Options under Article VI of the Plan, to interpret the provisions of
the Plan and any agreements relating to Options granted under the Plan, and to
administer the Plan. In making determinations of eligibility for the Plan, the
Board of Directors may consider the position and responsibilities of the
employee, the nature and value of his or her services and accomplishments, the
present and potential contribution of the employee to the success of the
Company, and such other factors as the Board of Directors may deem relevant.

         (b) Decisions of Board of Directors. All decisions made by the Board of
Directors pursuant to the provisions of the Plan shall be final, conclusive and
binding on all persons, including the Company, its shareholders and employees,
and beneficiaries of employees.

ARTICLE IV - SHARES SUBJECT TO THE PLAN

         4.1 (a) Number of Shares. Subject to adjustment as provided for in
Section 4.1(b), the maximum number of shares of Common Stock with respect to
which Options may be granted shall be 250,000 shares of Common Stock. Shares of
Common Stock shall be made available from the authorized but unissued shares of
the Company (including shares reacquired by the Company). If an Option granted
under the Plan shall expire or terminate for any reason, the shares subject to,
but not delivered, under such Option shall be available for other Options to be
issued under the Plan.

         (b) Adjustments. All as may be deemed appropriate by the Board of
Directors, the aggregate number of shares of Common Stock which may be issued
under the Plan, the number of shares covered by each outstanding Option, and the
price per share in each Option, may be proportionately adjusted for any increase
or decrease in the number of issued shares of Common


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Stock of the Company resulting from a subdivision or consolidation of shares or
any other capital adjustment, a stock split, the payment of a stock dividend, or
other increase or decrease in such shares effected without receipt of
consideration by the Company.

ARTICLE V - ELIGIBILITY

         5.1 The persons eligible to participate in the Plan and receive Options
under the Plan are officers and other employees of the Company and its
Subsidiaries, including directors who are full time employees, as determined by
the Board of Directors.

ARTICLE VI - STOCK OPTIONS

         6.1 Grant of Options. Subject to the limitations of the Plan, the Board
of Directors, after such consultation with and consideration of the
recommendations of management as the Board of Directors considers desirable,
shall select from eligible employees Participants to be granted Options and
determine the time when each Option shall be granted and the number of shares
subject to each Option. Options may be either Incentive Stock Options or
Non-Qualified Stock Options. More than one Option may be granted to the same
person. The Board of Directors may not grant a Participant Incentive Stock
Options which in the aggregate are first exercisable during any one calendar
year with respect to Common Stock the aggregate Fair Market Value of which
(determined as of the time of grant) exceeds $100,000.

         6.2 Option Agreements. Each Option under the Plan shall be evidenced by
an option agreement that shall be signed by an officer of the Company and the
Participant and shall contain such provisions as may be approved by the Board of
Directors. Any such option agreement may be amended from time to time as
approved by the Board of Directors and the Participant, provided that the terms
of such option agreement after being amended conform to the terms of the Plan.

         6.3 Option Price. The price at which shares of Common Stock may be
purchased upon exercise of an Option shall be not less than one hundred percent
(100%) of the Fair Market Value of such shares on the date such Option is
granted.

         6.4 Exercise of Options.

         (a) The period during which each Option may be exercised shall be fixed
by the Board of Directors at the time such Option is granted, but such period in
no event shall expire later than ten (10) years from the date the Option is
granted.

         (b) Subject to the terms and conditions of the option agreement and
unless canceled prior to exercise, each Option shall be exercisable in whole or
in part in installments at such time or times as the Board of Directors may
prescribe and specify in the applicable option agreement.

         (c) No shares shall be delivered pursuant to any exercise of an Option
until payment in full of the option price therefor is received by the Company.
Such payment shall be made in cash or through the delivery of shares of Common
Stock of the Company owned by the


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Participant for more than six (6) months with a value equal to the total option
price or a combination of cash and such shares. Any shares so delivered shall be
valued at their Fair Market Value on the exercise date. No Participant shall be
deemed to be a holder of any shares subject to any Option prior to the issuance
of such shares upon exercise of such Option.

         6.5 Ten-Percent Shareholder Rule. If a Participant owns more than ten
percent (10%) of the total combined voting power of all classes of the Company
or of any Subsidiary's stock at the time an Incentive Stock Option is granted to
such Participant, the option price to such Participant shall not be less than
one hundred ten percent (110%) of the Fair Market Value per share of the Common
Stock on the date of grant, and such Incentive Stock Option by its terms shall
not be exercisable after the expiration of five (5) years from the date of
grant.

         6.6 Non-Transferability of Options. No Option or any rights with
respect thereto shall be subject to any debts or liabilities of a Participant,
nor be assignable or transferable except by Will or the laws of descent and
distribution, nor be exercisable during the Participant's lifetime other than by
the Participant, nor shall Common Stock be issued to or in the name of one other
than the Participant; provided, however, that an Option may after the death or
disability of a Participant be exercised pursuant to Section 6.7; and provided
further that any Common Stock issued to a Participant hereunder may at the
request of the Participant, and with the consent of the Company, be issued in
the names of the Participant and one other person, as joint tenants with right
of survivorship and not as tenants in common, or in the name of a trust for the
benefit of the Participant or for the benefit of the Participant and others.

         6.7 Termination of Employment; Death and Disability. Subject to the
condition that no Option may be exercised in whole or in part after the
expiration of the option period specified in the applicable option agreement:

         (a) Except as hereinafter provided, an Option may be exercised by the
Participant only while such Participant is in the employ of the Company or a
Subsidiary. In the event that the employment of a Participant to whom an Option
has been granted under the Plan shall terminate (except as set forth below) such
Option may be exercised, to the extent that the Option was exercisable on the
date of termination of employment, only until the earlier of three (3) months
after such termination or the original expiration date of the Option; provided,
however, that if termination of employment results from death or total and
permanent disability, such three (3) month period shall be extended to twelve
(12) months.

         (b) In the event of the permanent disability of a Participant as
determined by the Board of Directors, an Option which is otherwise exercisable
may be exercised by the Participant's legal representative or guardian. In the
event of the death of the Participant, an Option which is otherwise exercisable
may be exercised by the person or persons whom the Participant shall have
designated in writing on forms prescribed by and filed with the Board of
Directors ("Beneficiaries"), or, if no such designation has been made, by the
person or persons to whom the Participant's rights shall have passed by Will or
the laws of descent and distribution ("Successors"). The Board of Directors may
require an indemnity and/or such evidence or other assurances as the Board of
Directors in its sole and absolute discretion may deem necessary in connection
with an exercise by a legal representative, guardian, Beneficiary or Successor.


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ARTICLE VII - GENERAL PROVISIONS

         7.1 Change in Control.

         (a) In the case of a Change in Control (as defined below) of the
Company, unless the Board of Directors determines otherwise, each Option then
outstanding shall become exercisable in full immediately prior to such Change in
Control.

         (b) Any determination by the Board of Directors made pursuant to
subsection (a) above may be made as to all outstanding Options or only as to
certain Options specified by the Board of Directors and any such determinations
shall be made in cases covered by subparagraphs 7.1(c)(i) and (ii) below prior
to or as soon as practicable after the occurrence of such event and in the cases
covered by subparagraphs 7. 1 (c) (iii) or (iv) prior to the occurrence of such
event.

         (c) A Change in Control shall occur if:

                  (i) Any "person" or "group of persons" as such terms are
defined in Section 13(d) and 14(c) of the Securities Exchange Act of 1934 (the
"Exchange Act") directly or indirectly purchases or otherwise becomes the
"beneficial owner" (as defined in the Exchange Act) or has the right to acquire
such beneficial ownership (whether or not such right is exercised immediately,
with the passage of time or subject to any condition) of voting securities
representing forty percent (40%) or more of the combined voting power of all
outstanding voting securities of the Company,

                  (ii) During any period of two consecutive calendar years the
individuals who at the beginning of such period constitute the Board of
Directors cease for any reason to constitute at least the majority of the
members thereof unless (1) there are five or more directors then still in office
who were directors at the beginning of the period and (2) the election or the
nomination for election by the Company's shareholders of each new director was
approved by at least two-thirds (2/3) of the directors then still in office who
were directors at the beginning of the period,

                  (iii) The shareholders of the Company shall approve an
agreement to merge or consolidate the Company with or into another corporation
as a result of which less than fifty percent (50%) of the outstanding voting
securities of the surviving or resulting entity are or are to be owned by the
former shareholders of the Company (excluding from former shareholders a
shareholder who is or as a result of the transaction in question, becomes an
affiliate as defined in Rule 12b-2 under the Exchange Act of any party to such
consolidation or merger), or

                  (iv) The shareholders of the Company shall approve the sale of
all or substantially all of the Company's business and/or assets to a person or
entity that is not a wholly-owned subsidiary of the Company.

         7.2 No Right of Continued Employment. Neither the establishment of the
Plan, the granting of Options or any action of the Company or of the Board of
Directors shall be held or

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construed to confer upon any person any legal right to be continued in the
employ of the Company or its Subsidiaries, each of which expressly reserves the
right to discharge any employee whenever the interest of any such company in its
sole discretion may so require without liability to such company or the Board of
Directors, except as to any rights that may be expressly conferred upon such
employee under the Plan.

         7.3 No Segregation of Cash or Shares. The Company shall not be required
to segregate any shares of Common Stock that may at any time be represented by
Options, and the Plan shall constitute an "unfunded" plan of the Company. No
employee shall have rights with respect to shares of Common Stock prior to the
delivery of such shares. The Company shall not, by any provisions of the Plan,
be deemed to be a trustee of any Common Stock or any other property and the
liabilities of the Company to any employee pursuant to the Plan shall be those
of a debtor pursuant to such contract obligations as are created by or pursuant
to the Plan, and the rights of any employee, former employee or beneficiary
under the Plan shall be limited to those of a general creditor of the Company.

         7.4 Delivery of Shares. No shares shall be delivered pursuant to any
exercise of an Option under the Plan unless the requirements of such laws and
regulations as may be deemed by the Board of Directors to be applicable thereto
are satisfied. All certificates for shares of Common Stock delivered under the
Plan shall be subject to such stock-transfer orders and other restrictions as
the Board of Directors may deem advisable under the rules, regulations, and
other requirements of the Securities and Exchange Commission, any stock exchange
or quotation system upon which the Common Stock is then listed, and any
applicable Federal or state securities law, and the Board of Directors may cause
a legend or legends to be put on any such certificates to make appropriate
reference to such restrictions.

         7.5 Governing Law. The Plan and all determinations made and action
taken pursuant thereto shall be governed by the laws of the State of Michigan
and construed in accordance therewith.

         7.6 Payments and Tax Withholding. The delivery of any shares of Common
Stock under the Plan shall be for the account of the Company and any such
delivery or distribution shall not be made until the recipient shall have made
satisfactory arrangements for the payment of any applicable withholding taxes.


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ARTICLE VIII - AMENDMENT AND TERMINATION

         8.1 Amendment or Termination. The Board of Directors may amend or
terminate the Plan provided, however, that no such amendment or termination
shall adversely affect any Option then in effect unless the prior approval of
the Participant so affected is obtained. No Option may be granted under the Plan
after December 31, 2013.


ARTICLE IX - EFFECTIVENESS OF PLAN

         9.1 The Plan was adopted by the Board of Directors on February 12, 2004
subject to the approval of the shareholders of the Company.


ARTICLE X - SEVERABILITY

         10.1 If any provision of the Plan, or any term or condition of any
Option granted under the Plan, is invalid, such provision, term, condition or
application shall to that extent be void (or, in the discretion of the Board of
Directors, such provision, term or condition may be amended so as to avoid such
invalidity or failure), and shall not affect other provisions, terms or
conditions or applications thereof, and to this extent such provisions, terms
and conditions are severable.


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