Registration No. 333-_____

As filed with the Securities and Exchange Commission on  March 31, 2003



                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM S-8

                             REGISTRATION STATEMENT
                        UNDER THE SECURITIES ACT OF 1933

                         SOUTHERN MICHIGAN BANCORP, INC.

             (Exact Name of Registrant as Specified in Its Charter)

                 MICHIGAN                                     38-2407501
      (State or Other Jurisdiction of                      (I.R.S. Employer
       Incorporation or Organization)                     Identification No.)

                              51 West Pearl Street
                            Coldwater, Michigan 49036
                                 (517) 279-5500
    (Address, Including Zip Code, and Telephone Number, Including Area Code,
                  of Registrant's Principal Executive Offices)


                         SOUTHERN MICHIGAN BANCORP, INC.
                             2000 STOCK OPTION PLAN
                            (Full Title of the Plan)

                                Danice Chartrand
                         Southern Michigan Bancorp, Inc.
                              51 West Pearl Street
                            Coldwater, Michigan 49036
                                 (517) 279-5500
 (Name, Address, Including Zip Code, and Telephone Number, Including Area Code,
                             of Agent For Service)


                         CALCULATION OF REGISTRATION FEE



 Title of Each Class of                                                            Proposed Maximum
   Securities To Be          Amount To Be               Proposed Maximum               Aggregate            Amount of
     Registered(1)           Registered(1)         Offering Price Per Share(2)     Offering Price(2)     Registration Fee
     -------------           -------------         ---------------------------     -----------------     ----------------
                                                                                             
     Common Stock,          110,000 shares               $18.12                      $1,993,200.00          $161.25
    $2.50 par value


- -------------------------
         (1) The number of shares registered may be adjusted to prevent dilution
from stock splits, stock dividends and similar transactions. Pursuant to Rule
416(a) under the Securities Act of 1933, as amended (the "Securities Act"), this
registration statement shall cover such additional shares.

         (2) Estimated pursuant to Rule 457(h) under the Securities Act solely
for the purpose of calculating the registration fee. The proposed maximum
offering price is based upon the average of the bid and ask price of the Common
Stock as reported on the OTC Bulletin Board on March 26, 2003 ($18.12).





                                     PART I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

The documents containing the information required in Part I of the Registration
Statement will be provided to each participant in the Southern Michigan Bancorp,
Inc. 2000 Stock Option Plan as required by Rule 428(b)(1). Those documents are
not being filed with the Securities and Exchange Commission (the "Commission")
in accordance with the instructions to Form S-8, but the documents constitute
(along with the documents incorporated by reference into the Registration
Statement pursuant to Item 3 of Part II hereof) a prospectus that meets the
requirements of Section 10(a) of the Securities Act of 1933.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT


ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

         The following documents filed by Southern Michigan Bancorp, Inc., a
Michigan corporation (Commission File No. 2-78178) (the "registrant") pursuant
to the Securities Exchange Act of 1934, as amended (the "Exchange Act"), are
incorporated in this Registration Statement by reference:

         (a) the registrant's Annual Report on Form 10-K for the year ended
December 31, 2002;

         (b) all other reports filed by the registrant pursuant to Section 13(a)
or 15(d) of the Exchange Act since December 31, 2002; and

         (c) the description of the registrant's common stock set forth under
"Item 1. Description of Registrant's Securities to be Registered" in its
registration statement on Form 8-A, filed with the Securities and Exchange
Commission on April 30, 2002, pursuant to Section 12(g) of the Exchange Act
which incorporates by reference to the description set forth under the caption
"THE COMMON STOCK" at page 10 of the registrant's Registration Statement on
Form S-3, Registration No. 333-51417, filed with the Securities and Exchange
Commission on April 30, 1998, and all amendments thereto or reports filed for
the purpose of updating such description.

         All documents subsequently filed by the registrant pursuant to Sections
13(a), 14, and 15(d) of the Exchange Act, prior to the filing of a
post-effective amendment which indicates that all securities offered have been
sold or which deregisters all securities then remaining unsold, shall be deemed
to be incorporated by reference in this Registration Statement and to be part
hereof from the date of filing such documents.

         Any statement contained in the documents incorporated, or deemed to be
incorporated, by reference herein or therein shall be deemed to be modified or
superseded for purposes of this Registration Statement and the prospectus to the
extent that a statement contained herein or therein or in any other subsequently
filed document which also is, or is deemed to be, incorporated by reference
herein or therein modifies or supersedes such statement. Any such


                                       1


statement so modified or superseded shall not be deemed, except as so modified
or superseded, to constitute a part of this Registration Statement and the
prospectus.

         The registrant shall furnish without charge to each person to whom the
prospectus is delivered, on the written or oral request of such person, a copy
of any or all of the documents incorporated by reference, other than exhibits to
such documents (unless such exhibits are specifically incorporated by reference
to the information that is incorporated). Requests should be directed to Jaylen
T. Johnson, Secretary, Southern Michigan Bancorp, Inc., 51 West Pearl Street,
Coldwater, Michigan 49036; telephone: (517) 279-5500.


ITEM 4.  DESCRIPTION OF SECURITIES.

         Not applicable.


ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

         Not applicable.


ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

         The Michigan Business Corporation Act, as amended ("MBCA"), provides
that a Michigan corporation, such as Southern Michigan Bancorp, Inc., may
indemnify a director, officer, employee or agent of the corporation (an
"Indemnitee") against the Indemnitee's expenses and judgments, fines and amounts
paid in settlement actually and reasonably incurred in connection with any
threatened, pending or completed action, suit or proceeding (other than an
action by or in the right of the corporation) involving the Indemnitee by reason
of the fact that the Indemnitee is or was a director, officer, employee or agent
of the corporation, if the Indemnitee acted in good faith and in a manner the
Indemnitee reasonably believed to be in or not opposed to the best interests of
the corporation or its shareholders and, with respect to any criminal action or
proceeding, had no reasonable cause to believe his or her conduct was unlawful.
The MBCA also provides that in derivative actions, a corporation may indemnify a
director, officer, employee or agent of the corporation against expenses
actually and reasonably incurred by the Indemnitee to the extent that the
Indemnitee is successful on the merits or otherwise in any such action, suit or
proceeding or in the defense of any claim, issue or matter therein. Under the
MBCA, no indemnification shall be made with respect to any claim, issue or
matter as to which an Indemnitee shall have been adjudged to be liable to the
corporation unless and only to the extent that the court shall determine upon
application that, despite the adjudication of liability but in view of all of
the circumstances of the case, the Indemnitee is fairly and reasonably entitled
to indemnity for such expenses which the court shall deem proper. The MBCA also
generally permits the advancement of reasonable expenses and empowers the
corporation to purchase and maintain directors' and officers' insurance.

         Article VIII of the Articles of Incorporation of the registrant
contains provisions authorizing indemnification of directors of the registrant.
Article V of the By-laws of the registrant contains provisions authorizing
indemnification of directors, officers, employees and



                                       2


agents of the registrant to the fullest extent authorized or permitted by the
MBCA and authorizes the registrant to purchase directors' and officers'
insurance.

         Section 209 of the MBCA provides that the articles of incorporation of
a corporation may contain a provision eliminating or limiting the personal
liability of a director to the corporation or its shareholders for money damages
for any action taken or failure to take any action as a director, provided that
such provision shall not eliminate or limit the liability of a director (i) for
the amount of a financial benefit received by a director to which such director
is not entitled, (ii) for an intentional infliction of harm on the corporation
or the shareholders, (iii) under Section 551 of the MBCA (relating to liability
for unauthorized acquisitions or redemptions of, or dividends on, capital stock
and loans to a director, officer, or employee of the corporation or of a
subsidiary of the corporation) or (iv) for an intentional criminal act. Article
VIII of the registrant's Articles of Incorporation include such a provision.

         Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
registrant pursuant to the provisions described in this Item 6 or otherwise, the
registrant has been advised that in the opinion of the Securities and Exchange
Commission such indemnification is against public policy as expressed in the
Securities Act of 1933 and is, therefore, unenforceable. In the event that a
claim for indemnification against such liabilities (other than the payment by
the registrant of expenses incurred or paid by a director, officer or
controlling person of the registrant in the successful defense of any action,
suit or proceeding) is asserted by such director, officer or controlling person
in connection with the securities being registered, the registrant will, unless
in the opinion of its counsel the matter has been settled by controlling
precedent, submit to a court of appropriate jurisdiction the question whether
such indemnification by it is against public policy as expressed in the
Securities Act and will be governed by the final adjudication of such issue.

         The registrant also maintains certain insurance policies that insure
its officers and directors against certain liabilities incurred in their
capacities as officers and directors.


ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

         Not applicable.


ITEM 8.  EXHIBITS.

         The following exhibits are furnished with this Registration Statement:

              Exhibit No.                          Description


                  4(a)              Articles of Incorporation are incorporated
                                    by reference to Exhibit 3 to Southern
                                    Michigan Bancorp, Inc.'s Annual Report on
                                    Form 10-K for the year ended December 31,
                                    1991 and Exhibit 3 to Form S-3 filed April
                                    30, 1998.

                                       3


                  (4)(b)            Amended and Restated By-Laws are
                                    incorporated by reference to Exhibit 3 to
                                    Southern Michigan Bancorp, Inc.'s Annual
                                    Report on Form 10-K for the year ended
                                    December 31, 1997.

                  (4)(c)            Southern Michigan Bancorp, Inc.'s specimen
                                    stock certificate is incorporated by
                                    reference to Exhibit 3 to Southern Michigan
                                    Bancorp, Inc.'s Registration Statement on
                                    Form 8-A filed April 30, 2002.

                  (5)(a)            Opinion and consent of Miller, Canfield,
                                    Paddock and Stone, P.L.C.*

                  (23)(a)           Consent of Miller, Canfield, Paddock and
                                    Stone, P.L.C. (contained in Exhibit (5)(a)).

                  (23)(b)           Consent of Crowe, Chizek and Company LLP.*

                  (24)              Powers of attorney (contained in the
                                    signature pages hereto).*

                  (99)              Southern Michigan Bancorp, Inc. 2000 Stock
                                    Option Plan is incorporated by reference to
                                    Exhibit 10(b) to the Company's Annual Report
                                    on Form 10-K for the year ended December 31,
                                    1999.
- -----------------------------

*        Filed herewith.


ITEM 9.  UNDERTAKINGS.

         The undersigned registrant hereby undertakes:

                  (1) To file, during any period in which offers or sales are
         being made, a post-effective amendment to this registration statement:

                           (i) To include any prospectus required by Section
                  10(a)(3) of the Securities Act of 1933;

                           (ii) To reflect in the prospectus any facts or events
                  arising after the effective date of the registration statement
                  (or the most recent post-effective amendment thereof) which,
                  individually or in the aggregate, represent a fundamental
                  change in the information set forth in the registration
                  statement;



                                       4


                           (iii) To include any material information with
                  respect to the plan of distribution not previously disclosed
                  in the registration statement or any material change to such
                  information in the registration statement;

         Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not
         apply if the information required to be included in a post-effective
         amendment by those paragraphs is contained in periodic reports filed by
         the registrant pursuant to Section 13 or Section 15(d) of the
         Securities Exchange Act of 1934 that are incorporated by reference into
         the registration statement.

                  (2) That, for the purpose of determining any liability under
         the Securities Act of 1933, each such post-effective amendment shall be
         deemed to be a new registration statement relating to the securities
         offered therein, and the offering of such securities at that time shall
         be deemed to be the initial bona fide offering thereof.

                  (3) To remove from registration by means of a post-effective
         amendment any of the securities being registered which remain unsold at
         the termination of the offering.

         The undersigned registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act of 1933, each filing of the
registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Securities Exchange Act of 1934 (and, where applicable, each filing of an
employee benefit plan's annual report pursuant to Section 15(d) of the
Securities Exchange Act of 1934) that is incorporated by reference in the
registration statement shall be deemed to be a new registration statement
relating to the securities offered therein, and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.

         Insofar as indemnification for liabilities arising under the Securities
Act of 1933 may be permitted to directors, officers and controlling persons of
the registrant pursuant to the foregoing provisions, or otherwise, the
registrant has been advised that in the opinion of the Securities and Exchange
Commission such indemnification is against public policy as expressed in the
Securities Act of 1933 and is, therefore, unenforceable. In the event that a
claim for indemnification against such liabilities (other than the payment by
the registrant of expenses incurred or paid by a director, officer or
controlling person of the registrant in the successful defense of any action,
suit or proceeding) is asserted by such director, officer or controlling person
in connection with the securities being registered, the registrant will, unless
in the opinion of its counsel the matter has been settled by controlling
precedent, submit to a court of appropriate jurisdiction the question whether
such indemnification by it is against public policy as expressed in the Act and
will be governed by the final adjudication of such issue.




                                       5




                                   SIGNATURES

         The registrant. Pursuant to the requirements of the Securities Act of
1933, the registrant certifies that it has reasonable grounds to believe that it
meets all of the requirements for filing on Form S-8 and has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Coldwater, State of Michigan, on this 31st day
of March, 2003.

                                               SOUTHERN MICHIGAN BANCORP, INC.,
                                               a Michigan corporation


                                               By:      /s/ John H. Castle
                                                        ------------------------
                                                        John H. Castle
                                               Its:     Chief Executive Officer


         Directors and Officers of the registrant. Pursuant to the requirements
of the Securities Act of 1933, this Registration Statement has been signed below
by the following persons in the capacities indicated and on the dates indicated
below. By so signing, each of the undersigned, in his or her capacity as a
director or officer, or both, as the case may be, of the registrant, does hereby
appoint John H. Castle, Kurt G. Miller and Danice Chartrand, and each of them
severally, his or her true and lawful attorney to execute in his or her name,
place and stead, in his or her capacity as a director or officer, or both, as
the case may be, of the registrant, any and all amendments to this Registration
Statement (including post-effective amendments thereto) and all instruments
necessary or incidental in connection therewith, and to file the same with the
Securities and Exchange Commission. Each of said attorneys shall have full power
and authority to do and perform in the name and on behalf of each of the
undersigned, in any and all capacities, every act whatsoever requisite or
necessary to be done in the premises as fully, and for all intents and purposes,
as each of the undersigned might or could do in person, the undersigned hereby
ratifying and approving the acts of said attorneys and each of them.



             Signatures                                       Title                               Date
             ----------                                       -----                               ----
                                                                                        
Principal Executive Officer:


/s/ John H. Castle                                 Chief Executive Officer and                March 31, 2003
- -----------------------------------------          Director
John H. Castle


Principal Financial Officer & Principal
Accounting Officer:


/s/ Danice Chartrand                               Chief Financial Officer                    March 31, 2003
- -----------------------------------------
Danice Chartrand

/s/ Kurt G. Miller                                 President and Director                     March 31, 2003
- -----------------------------------------
Kurt G. Miller



                             S-1







         Signatures                                              Title                                Date
         ----------                                              -----                                ----
                                                                                            
/s/ Jaylen T. Johnson                                  Executive Vice-President, Chief            March 31, 2003
- --------------------------------------------           Operating Officer and Secretary
Jaylen T. Johnson


/s/ Marcia Albright                                    Director                                   March 31, 2003
- --------------------------------------------
Marcia Albright


/s/ James P. Briskey                                   Director                                   March 31, 2003
- --------------------------------------------
James P. Briskey


/s/ H. Kenneth Cole                                    Director                                   March 31, 2003
- --------------------------------------------
H. Kenneth Cole


/s/ William E. Galliers                                Director                                   March 31, 2003
- --------------------------------------------
William E. Galliers


/s/ Nolan E. Hooker                                    Director                                   March 31, 2003
- --------------------------------------------
Nolan E. Hooker


/s/ Gregory J. Hull                                    Director                                   March 31, 2003
- --------------------------------------------
Gregory J. Hull


/s/ Thomas E. Kolassa                                  Director                                   March 31, 2003
- --------------------------------------------
Thomas E. Kolassa


/s/ Freeman E. Riddle                                  Director                                   March 31, 2003
- --------------------------------------------
Freeman E. Riddle





                                      S-2






                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                    Form S-8






                                Index to Exhibits
                                    Exhibits






                         SOUTHERN MICHIGAN BANCORP, INC.
                            (A Michigan corporation)
                              51 West Pearl Street
                            Coldwater, Michigan 49036


                                INDEX TO EXHIBITS


               Exhibit No.                       Description
               -----------                       -----------

                  4(a)              Articles of Incorporation are incorporated
                                    by reference to Exhibit 3 to Southern
                                    Michigan Bancorp, Inc.'s Annual Report on
                                    Form 10-K for the year ended December 31,
                                    1991 and Exhibit 3 to Form S-3 filed April
                                    30, 1998.

                  (4)(b)            Amended and Restated By-Laws are
                                    incorporated by reference to Exhibit 3 to
                                    Southern Michigan Bancorp, Inc.'s Annual
                                    Report on Form 10-K for the year ended
                                    December 31, 1997.

                  (4)(c)            Southern Michigan Bancorp, Inc.'s specimen
                                    stock certificate is incorporated by
                                    reference to Exhibit 3 to Southern Michigan
                                    Bancorp, Inc.'s Registration Statement on
                                    Form 8-A filed April 30, 2002.

                  (5)(a)            Opinion and consent of Miller, Canfield,
                                    Paddock and Stone, P.L.C.*

                  (23)(a)           Consent of Miller, Canfield, Paddock and
                                    Stone, P.L.C. (contained in Exhibit (5)(a)).

                  (23)(b)           Consent of Crowe, Chizek and Company LLP.*

                  (24)              Powers of attorney (contained in the
                                    signature pages hereto).*

                  (99)              Southern Michigan Bancorp, Inc. 2000 Stock
                                    Option Plan is incorporated by reference to
                                    Exhibit 10(b) to the Company's Annual Report
                                    on Form 10-K for the year ended December 31,
                                    1999.
- -----------------------------

*        Filed herewith.


                                      E-1