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    AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON NOVEMBER 19, 2001
                                                      REGISTRATION NO. 333-_____
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549
                             ----------------------

                                    FORM S-8

                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933
7                             ----------------------

                                 TENNANT COMPANY
             (Exact name of registrant as specified in its charter)

                MINNESOTA                                   41-0572550
     (State or other jurisdiction of                     (I.R.S. Employer
      incorporation or organization)                   Identification No.)

          701 NORTH LILAC DRIVE                               55440
              P.O. BOX 1452                                 (Zip Code)
          MINNEAPOLIS, MINNESOTA
 (Address of principal executive offices)

                                 TENNANT COMPANY
                 AMENDED AND RESTATED 1999 STOCK INCENTIVE PLAN
                            (Full title of the plan)

                                JAMES J. SEIFERT
                  VICE PRESIDENT, GENERAL COUNSEL AND SECRETARY
                                 TENNANT COMPANY
                              701 NORTH LILAC DRIVE
                                  P.O. BOX 1452
                          MINNEAPOLIS, MINNESOTA 55440
                     (Name and address of agent for service)

                                 (763) 540-1200
          (Telephone number, including area code, of agent for service)
                             ----------------------

                         CALCULATION OF REGISTRATION FEE

<Table>
<Caption>
======================== ================== ======================= ========================== =====================
       Title of               Amount           Proposed Maximum         Proposed Maximum            Amount of
     Securities to             to be            Offering Price         Aggregate Offering          Registration
     be Registered         Registered(1)         Per Share(2)               Price(2)                   Fee
- ------------------------ ------------------ ----------------------- -------------------------- ---------------------
                                                                                        
   Common Stock, par          475,000
 value $.375 per share         Shares               $33.90               $16,102,500.00             $4,025.63
======================== ================== ======================= ========================== =====================
</Table>

(1)      This registration statement relates to 475,000 additional shares of the
         registrant's Common Stock to be offered pursuant to the registrant's
         Amended and Restated 1999 Stock Incentive Plan.

(2)      Estimated solely for the purpose of calculating the registration fee
         pursuant to Rules 457(c) and (h)(1) under the Securities Act of 1933,
         based on the average of the high and low sale prices per share of the
         registrant's Common Stock on November 15, 2001, as reported on the New
         York Stock Exchange Composite Tape.

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                                     PART II

                           INFORMATION REQUIRED IN THE
                             REGISTRATION STATEMENT


ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

         The following documents previously filed (File No. 0-4804) with the
Securities and Exchange Commission (the "Commission") pursuant to the Securities
Exchange Act of 1934 (the "Exchange Act") are, as of their respective dates,
incorporated by reference in this registration statement:

                  (a) The Annual Report on Form 10-K of Tennant Company (the
         "Company") for the fiscal year ended December 31, 2000 (which
         incorporates by reference certain portions of the Company's 2000 Annual
         Report to Shareholders, including financial statements and accompanying
         information, and certain portions of the Company's definitive proxy
         statement for the Company's 2001 Annual Meeting of Shareholders);

                  (b) All other reports filed pursuant to Section 13(a) or 15(d)
         of the Exchange Act since the end of the fiscal year covered by the
         Annual Report referred to in (a) above; and

                  (c) The description of the Company's common stock contained in
         a registration statement filed pursuant to the Exchange Act, together
         with any amendments or reports filed for the purpose of updating that
         description.

         In addition, all documents filed by the Company pursuant to Sections
13(a), 13(c), 14, or 15(d) of the Exchange Act after the date of this
registration statement and before the filing of a post-effective amendment that
indicates that all shares of common stock offered have been sold, or that
deregisters all shares of common stock then remaining unsold, shall be deemed to
be incorporated by reference in, and to be a part of, this registration
statement from the date of filing of those documents.

         Any statement contained in a document incorporated, or deemed to be
incorporated, by reference herein shall be deemed to be modified or superseded
for purposes of this registration statement to the extent that a statement
contained herein or incorporated herein by reference or in any other
subsequently filed document that is or is deemed to be incorporated by reference
herein modifies or supersedes that statement. Any statement so modified or
superseded shall not be deemed, except as so modified or superseded, to
constitute a part of this registration statement.

ITEM 4.  DESCRIPTION OF SECURITIES.

         Not Applicable.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

         James J. Seifert, Vice President, General Counsel and Secretary of the
Company, beneficially owns shares of the Company's common stock having a fair
market value of more than $33,000.

ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

         Article VI of the Company's Restated By-Laws provides that the Company
shall indemnify its directors and officers to the full extent required by
Minnesota Statutes, Section 302A.521, or by other provisions of law. Section
302A.521 requires the Company to indemnify a person made or threatened to be
made a party to a


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proceeding by reason of the former or present official capacity of the person
with respect to the Company against judgments, penalties, fines (including,
without limitation, excise taxes assessed against the person with respect to an
employee benefit plan), settlements, and reasonable expenses, including
attorneys' fees and disbursements, incurred by the person in connection with the
proceeding, if certain criteria are met. These criteria, all of which must be
met by the person seeking indemnification, are:

                  (a) the person has not been indemnified by another
         organization for the same judgments, penalties, fines, settlements, and
         expenses;

                  (b) the person must have acted in good faith;

                  (c) no improper personal benefit was obtained by the person
         and, if applicable, certain statutory conflict-of-interest provisions
         have been satisfied;

                  (d) in the case of a criminal proceeding, the person had no
         reasonable cause to believe that the conduct was unlawful; and

                  (e) the person acted in a manner he or she reasonably believed
         was in the best interests of the corporation or, in certain limited
         circumstances, not opposed to the best interests of the corporation.

         The determination as to eligibility for indemnification is made by the
members of the Company's board of directors, or a committee thereof, who are at
the time not parties to the proceedings under consideration, by special legal
counsel, by the shareholders who are not parties to the proceedings or by a
court.

         Article VIII of the Company's Restated Articles of Incorporation
provides that no director shall be personally liable to the Company or its
shareholders for monetary damages for breach of fiduciary duty as director,
except:

                  (a) any breach of the director's duty of loyalty to the
         Company or its shareholders;

                  (b) acts or omissions not in good faith or which involve
         intentional misconduct or a knowing violation of law;

                  (c) dividends, stock repurchases and other distributions made
         in violation of Minnesota law or for violations of the Minnesota
         securities laws;

                  (d) any transaction from which the director derived an
         improper personal benefit; or

                  (e) any act or omission occurring before the effective date of
         the provision in the Company's Restated Articles of Incorporation
         limiting such liability.

         Article VIII does not affect the availability of equitable remedies,
such as an action to enjoin or rescind a transaction involving a breach of
fiduciary duty, although, as a practical matter, equitable relief may not be
available. Nor does this Article limit the liability of directors for violations
of, or relieve them from the necessity of complying with, federal securities
laws.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

         Not Applicable.


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ITEM 8.  EXHIBITS.

         Exhibit        Description
         -------        -----------

         4              Rights Agreement, dated as of November 19, 1996, as
                        amended, between the Company and Wells Fargo Bank
                        Minnesota, National Association (f/k/a Norwest Bank
                        Minnesota, National Association) (incorporated by
                        reference to Exhibit 1 to Form 8-A dated November 26,
                        1996, as amended by Form 8-A/A dated November 18, 1999).

         5              Opinion of James J. Seifert.

         23.1           Consent of James J. Seifert (included in Exhibit 5).

         23.2           Independent Auditors' Consent.

         24             Powers of Attorney.

         99             Tennant Company Amended and Restated 1999 Stock
                        Incentive Plan.

ITEM 9. UNDERTAKINGS.

         A. 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. Notwithstanding the foregoing, any increase or
                  decrease in volume of securities offered (if the total dollar
                  value of securities offered would not exceed that which was
                  registered) and any deviation from the low or high end of the
                  estimated maximum offering range may be reflected in the form
                  of prospectus filed with the Securities and Exchange
                  Commission pursuant to Rule 424(b) if, in the aggregate, the
                  changes in volume and price represent no more than a twenty
                  percent change in the maximum aggregate offering price set
                  forth in the "Calculation of Registration Fee" table in the
                  effective registration statement; and

                           (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 with or furnished to the
Securities and Exchange Commission by the registrant pursuant to Section 13 or
Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by
reference in the registration statement.

                  (2) That, for the purpose of determining any liability under
         the Securities Act of 1933, each post-effective amendment shall be
         deemed to be a new registration statement relating to the securities
         offered

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         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.

         B. The 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
herein, and the offering of such securities at that time shall be deemed to be
the initial BONA FIDE offering thereof.

         C. 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 Company 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 any 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 of 1933 and will be governed by the final adjudication of such
issue.


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                                   SIGNATURES

         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 Minneapolis, State of Minnesota, on November 1, 2001.

                                          TENNANT COMPANY


                                          By   /s/ James J. Seifert
                                             -----------------------------------
                                             Its Vice President, General Counsel
                                             and Secretary

         Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities and on the date indicated.

<Table>
<Caption>
SIGNATURE                                 TITLE

                                       
/s/ Janet M. Dolan                        President and Chief Executive Officer
- --------------------------------          (Principal Executive Officer)
Janet M. Dolan


/s/ Anthony T. Brausen                    Vice President, Chief Financial Officer and Treasurer
- --------------------------------          (Principal Financial Officer)
Anthony T. Brausen


/s/ Gregory M. Siedschlag                 Corporate Controller and Principal Accounting Officer
- --------------------------------          (Principal Accounting Officer)
Gregory M. Siedschlag
</Table>


David C. Cox                    )
Andrew P. Czajkowski            )
Janet M. Dolan                  )
James T. Hale                   )
Pamela K. Knous                 )         A majority of the Board of Directors*
William I. Miller               )
Edwin L. Russell                )
Stephen G. Shank                )
Frank L. Sims                   )


* James J. Seifert, by signing his name hereto, hereby signs this document on
behalf of each of the above-named officers or directors of the registrant under
powers of attorney executed by those persons.



                              By   /S/ JAMES J. SEIFERT
                                 -----------------------------------------------
                                                 James J. Seifert
                                  Vice President, General Counsel and Secretary,
                                                 Attorney in Fact

<Page>

                                INDEX TO EXHIBITS



<Table>
<Caption>
   EXHIBIT                                     DESCRIPTION

                                                                                  
        4         Rights Agreement, dated as of November 19, 1996, as amended,
                  between the Company and Wells Fargo Bank Minnesota, National
                  Association (f/k/a Norwest Bank Minnesota, National
                  Association) (incorporated by reference to Exhibit 1 to Form
                  8-A dated November 26, 1996, as amended by Form 8-A/A dated
                  November 18, 1999)................................................... Incorporated.by Reference

        5         Opinion of James J. Seifert.......................................... Filed.Electronically

       23.1       Consent of James J. Seifert (included in Exhibit 5)

       23.2       Independent Auditors' Consent........................................ Filed.Electronically

       24         Powers of Attorney................................................... Filed.Electronically

       99         Tennant Company Amended and Restated 1999 Stock Incentive Plan....... Filed Electronically
</Table>


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