<PAGE>



      As filed with the Securities and Exchange Commission on June 15, 2001
                                            REGISTRATION STATEMENT NO. 333-53848

===============================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                    ----------------------------------------

                        POST-EFFECTIVE AMENDMENT NO. 1 TO
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                    ----------------------------------------

                            HARVARD BIOSCIENCE, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

         DELAWARE                                        04-3306140
(STATE OF INCORPORATION)                   (I.R.S. EMPLOYER IDENTIFICATION NO.)


                              84 OCTOBER HILL ROAD
                       HOLLISTON, MASSACHUSETTS 01746-1371
                                 (508) 893-8066
       (ADDRESS, INCLUDING ZIP CODE, AND TELEPHONE NUMBER, INCLUDING AREA
               CODE, OF REGISTRANT'S PRINCIPAL EXECUTIVE OFFICES)

          HARVARD BIOSCIENCE, INC. 2000 STOCK OPTION AND INCENTIVE PLAN
            HARVARD APPARATUS, INC. 1996 STOCK OPTION AND GRANT PLAN
              HARVARD BIOSCIENCE, INC. EMPLOYEE STOCK PURCHASE PLAN
                            (FULL TITLE OF THE PLAN)

          -------------------------------------------------------------

                                 CHANE GRAZIANO
                             CHIEF EXECUTIVE OFFICER
                            HARVARD BIOSCIENCE, INC.
                              84 OCTOBER HILL ROAD
                       HOLLISTON, MASSACHUSETTS 01746-1371
                                 (508) 893-8066
            (NAME, ADDRESS, INCLUDING ZIP CODE, AND TELEPHONE NUMBER,
                   INCLUDING AREA CODE, OF AGENT FOR SERVICE)

                    ----------------------------------------

                                  With copy to:
                              H. DAVID HENKEN, P.C.
                               GOODWIN PROCTER LLP
                                 EXCHANGE PLACE
                        BOSTON, MASSACHUSETTS 02109-2881
                                 (617) 570-1000

                    ----------------------------------------

                         CALCULATION OF REGISTRATION FEE

<TABLE>
<CAPTION>

===================================================================================================================================
 Title of Securities Being         Amounts to be         Proposed Maximum Offering      Proposed Maximum               Amount of
        Registered                Registered (1)            Price Per Share (2)      Aggregate Offering Price       Registration Fee
-----------------------------------------------------------------------------------------------------------------------------------
<S>                            <C>                     <C>                         <C>                            <C>

  Common Stock, par value        4,849,096 shares                $9.815                   $47,593,877
      $.01 per share                                                                                                 $12,441 (3)
                                  263,202 shares                 $8.225                   $2,164,837

    Plan Interests (4)                N/A (4)                    N/A (4)                    N/A (4)                    N/A (4)
===================================================================================================================================
</TABLE>


(1)  This Registration Statement also relates to such indeterminate number of
     additional shares of Common Stock, par value $.01 per share, of Harvard
     Bioscience, Inc. (the "Common Stock") as may be required pursuant to the
     Harvard Bioscience, Inc. 2000 Stock Option and Incentive Plan, the Harvard
     Apparatus, Inc. 1996 Stock Option and Grant Plan and the Harvard
     Bioscience, Inc. Employee Stock Purchase Plan (the "Plans") in the event of
     a stock dividend, reverse stock split, split-up, recapitalization,
     forfeiture of stock under the Plans or other similar event.

(2)  This estimate is made pursuant to Rule 457(c) and (h) under the Securities
     Act of 1933 (the "Securities Act") solely for the purposes of determining
     the amount of the registration fee. The registration fee for 4,849,096
     shares previously registered in connection with the initial filing of this
     Registration Statement was calculated based upon the average of the high
     and low sale price for a share of Common Stock, as reported on the Nasdaq
     National Market System as of a date within five business days prior to such
     initial filing. The registration fee for 263,202 additional shares being
     registered in connection with this Post-Effective Amendment No. 1 to the
     Registration Statement is calculated based upon the average of the high and
     low sale price for a share of Common Stock, as reported on the Nasdaq
     National Market System as of a date within five business days prior to
     filing this Post-Effective Amendment No. 1 to the Registration Statement.

(3)  Includes $11,899 paid prior to the initial filing of this Registration
     Statement and $542 being paid in connection with this Post-Effective
     Amendment No. 1 to the Registration Statement.

(4)  In addition, pursuant to Rule 416(c) under the Securities Act, this
     Registration Statement also covers an indeterminate amount of interests to
     be offered or sold pursuant to the Harvard Bioscience, Inc. Employee Stock
     Purchase Plan. In accordance with Rule 457(h)(2), no separate fee
     calculation is made for plan interests.

===============================================================================



<PAGE>


         THIS POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-8 IS BEING FILED IN
CONNECTION WITH THE REGISTRATION OF 263,202 ADDITIONAL SHARES UNDER THE HARVARD
BIOSCIENCE, INC. 2000 STOCK OPTION AND INCENTIVE PLAN AND AMENDS AND RESTATES
ELEMENTS OF THE FEE CALCULATION TABLE AND ASSOCIATED FOOTNOTES, ITEM 3, ITEM 6,
ITEM 8, AND THE EXHIBIT INDEX OF THE REGISTRATION STATEMENT ON FORM S-8 OF THE
REGISTRANT PERTAINING TO THE HARVARD BIOSCIENCE, INC. 2000 STOCK OPTION AND
INCENTIVE PLAN, THE HARVARD APPARATUS, INC. 1996 STOCK OPTION AND GRANT PLAN AND
THE HARVARD BIOSCIENCE, INC. EMPLOYEE STOCK PURCHASE PLAN FILED ON JANUARY 17,
2001 UNDER FILE NUMBER 333-53848 ("ORIGINAL REGISTRATION STATEMENT").

                                     PART I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS


Item 1.  PLAN INFORMATION.*

Item 2.  REGISTRANT INFORMATION AND EMPLOYEE PLAN ANNUAL INFORMATION.*

         * Information required by Part I to be contained in Section 10(a)
Prospectuses is omitted from this Registration Statement in accordance with Rule
428 under the Securities Act of 1933 (the "Securities Act") and the Introductory
Note to Part I of Form S-8.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT


Item 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

         Harvard Bioscience, Inc. (the "Registrant") hereby incorporates by
reference the following documents which have previously been filed with the
Securities and Exchange Commission (the "Commission"):

(a)      the Registrant's Annual Report on Form 10-K for the fiscal year ended
         December 31, 2000 as filed with the Commission on April 2, 2001
         pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of
         1934, as amended (the "Exchange Act");

(b)      all other reports filed with the Commission by the Registrant pursuant
         to Section 13(a) or 15(d) of the Exchange Act since December 31, 2000;
         and

(c)      the description of the Registrant's Common Stock contained in the
         Registration Statement on Form 8-A, dated November 8, 2000, as filed
         with the Commission on November 9, 2000 pursuant to Section 12(g) of
         the Exchange Act and any amendments or reports filed for the purpose of
         updating such description.

         In addition, all documents subsequently filed with the Commission by
the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange
Act, prior to the filing of a post-effective amendment hereto that indicates
that all securities offered hereunder 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 a part hereof from the date
of filing of such documents. Any statement contained in a document incorporated
by reference herein shall be deemed to be modified or superseded for purposes
hereof to the extent that a statement contained herein or in any subsequently
filed document which also is incorporated by reference herein modifies or
supersedes such 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.

                                       2


<PAGE>

Item 4.  DESCRIPTION OF SECURITIES.

         Not Applicable.

Item 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

         Not Applicable.

Item 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

         In accordance with Section 145 of the General Corporation Law of the
State of Delaware (the "DGCL"), Article VII of the Registrant's Second Amended
and Restated Certificate of Incorporation (the "Certificate") provides that no
director of the Registrant shall be personally liable to the Registrant or its
stockholders for monetary damages for breach of fiduciary duty as a director,
except for liability (i) for any breach of the director's duty of loyalty to the
Registrant or its stockholders, (ii) for acts or omissions not in good faith or
which involve intentional misconduct or a knowing violation of law, (iii) in
respect of certain unlawful dividend payments or stock redemptions or
repurchases, or (iv) for any transaction from which the director derived an
improper personal benefit. In addition, the Certificate provides that if the
DGCL is amended to authorize the further elimination or limitation of the
personal liability of directors, then the liability of a director of the
Registrant shall be eliminated or limited to the fullest extent permitted by the
DGCL, as so amended.

         Article V of the Registrant's Amended and Restated By-laws (the
"By-laws") provides for indemnification by the Registrant of its directors,
officers and certain non-officer employees under certain circumstances against
expenses (including attorneys fees, judgments, fines and amounts paid in
settlement) reasonably incurred in connection with the defense or settlement of
any threatened, pending or completed legal proceeding in which any such person
is involved by reason of the fact that such person is or was a director, an
officer or an employee of the Registrant if such person acted in good faith and
in a manner he or she reasonably believed to be in, or not opposed to, the best
interests of the Registrant, and, with respect to criminal actions or
proceedings, that such person had no reasonable cause to believe his or her
conduct was unlawful. Registrant has also obtained directors' and officers'
insurance against certain liabilities.

         The Registrant has entered into indemnification agreements with each of
its directors reflecting the foregoing provisions of its By-laws and requiring
the advancement of expenses in proceedings, if such person had no reasonable
cause to believe his or her conduct was unlawful.

         Under Section 8 of the Underwriting Agreement filed as Exhibit 1.1 to
the Registrant's Registration Statement on Form S-1 (File No. 333-45996), the
Underwriters (as defined therein) have agreed to indemnify, under certain
conditions, the Registrant, its directors, certain officers and persons who
control the Registrant within the meaning of the Securities Act against certain
liabilities.

Item 7.  EXEMPTION FROM REGISTRATION CLAIMED.

         Not applicable.

                                       3


<PAGE>

Item 8.  EXHIBITS.

         The following is a complete list of exhibits filed or incorporated by
reference as part of this Registration Statement.


<TABLE>
<CAPTION>

    EXHIBIT
<S>             <C>

      +3.2       Second Amended and Restated Certificate of Incorporation of Registrant.

      +3.3       Amended and Restated By-laws of Registrant.

     **5.1       Opinion of Goodwin Procter  LLP as to the legality of the securities being registered.

     *10.1       Harvard Apparatus, Inc. 1996 Stock Option and Grant Plan.

     *10.2       Harvard Bioscience, Inc. 2000 Stock Option and Incentive Plan.

     *10.3       Harvard Bioscience, Inc. Employee Stock Purchase Plan.

    **23.1       Consent of Counsel (included in Exhibit 5.1 hereto).

      23.2       Consent of KPMG LLP.

    **24.1       Powers of Attorney.
</TABLE>


+        Incorporated by reference to the relevant exhibit to the Registrant's
         Annual Report on Form 10-K for the fiscal year ended December 31, 2000,
         as filed with the Commission.

*        Incorporated by reference to the relevant exhibit to the Registrant's
         Registration Statement on Form S-1 (File No. 333-45996), as amended, as
         filed with the Commission.

**       Previously filed.

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;

                           (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 Commission pursuant to Rule
                  424(b) if, in the aggregate, the changes in volume and price
                  represent no more than a 20 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) herein 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 undersigned registrant pursuant to Section 13 or
         Section 15(d) of the Exchange Act that are incorporated by reference in
         the Registration Statement;

                  (2) That, for the purpose of determining any liability under
         the Securities Act, 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; and

                                       4


<PAGE>

                  (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 undersigned registrant hereby undertakes that, for
                  purposes of determining any liability under the Securities
                  Act, each filing of the registrant's annual report pursuant to
                  Section 13(a) or 15(d) of the Exchange Act (and, where
                  applicable, each filing of an employee benefit plan's annual
                  report pursuant to Section 15(d) of the Exchange Act) 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.

         (c)      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
                  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, 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.

                                       5


<PAGE>


                                   SIGNATURES


         Pursuant to the requirements of the Securities Act, Harvard Bioscience,
Inc. 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 Holliston, Massachusetts on June 15, 2001.


                                        HARVARD BIOSCIENCE, INC.



                                        By: /s/ James Warren
                                            -----------------------------------
                                            James Warren
                                            CHIEF FINANCIAL OFFICER

         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 dates indicated.


<TABLE>
<CAPTION>

              SIGNATURE                                            TITLE                                DATE
              ---------                                            -----                                ----
<S>                                       <C>                                                   <C>


                 ***                         Chief Executive Officer and Director                   June 15, 2001
--------------------------------------       (Principal Executive Officer)
Chane Graziano                               


/s/ James Warren                             Chief Financial Officer                                June 15, 2001
--------------------------------------       (Principal Financial Officer and Principal
James Warren                                 Accounting Officer)


                 ***                         President and Director                                 June 15, 2001
--------------------------------------
David Green


                 ***                         Director                                               June 15, 2001
--------------------------------------
Christopher W. Dick


                 ***                         Director                                               June 15, 2001
--------------------------------------
Richard C. Klaffky, Jr.


                 ***                         Director                                               June 15, 2001
--------------------------------------
Robert Dishman


                 ***                         Director                                               June 15, 2001
--------------------------------------
John F. Kennedy


                 ***                         Director                                               June 15, 2001
--------------------------------------
Earl R. Lewis
</TABLE>




***By:  /s/ James Warren
        -------------------------------
        James Warren
        ATTORNEY-IN-FACT



<PAGE>


         THE PLANS. Pursuant to the requirements of the Securities Act of 1933,
the trustees (or other persons who will administer the Plans) have duly caused
this registration statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in Holliston, Massachusetts, on June 15, 2001.


                               HARVARD BIOSCIENCE, INC.,
                               as administrator of the Harvard Bioscience, Inc.
                               2000 Stock Option and Incentive Plan



                               By:  /s/ James Warren
                                   --------------------------------------------
                                   James Warren
                                   Chief Financial Officer



                               HARVARD BIOSCIENCE, INC.,
                               as administrator of the Harvard Apparatus, Inc.
                               1996 Stock Option and Grant Plan



                               By: /s/ James Warren
                                   --------------------------------------------
                                   James Warren
                                   Chief Financial Officer



                               HARVARD BIOSCIENCE, INC.,
                               as administrator of the Harvard Bioscience, Inc.
                               Employee Stock Purchase Plan



                               By: /s/ James Warren
                                   --------------------------------------------
                                   James Warren
                                   Chief Financial Officer



<PAGE>


                                  EXHIBIT INDEX


<TABLE>
<CAPTION>

    EXHIBIT
<S>             <C>

      +3.2       Second Amended and Restated Certificate of Incorporation of Registrant.

      +3.3       Amended and Restated By-laws of Registrant.

     **5.1       Opinion of Goodwin Procter  LLP as to the legality of the securities being registered.

     *10.1       Harvard Apparatus, Inc. 1996 Stock Option and Grant Plan.

     *10.2       Harvard Bioscience, Inc. 2000 Stock Option and Incentive Plan.

     *10.3       Harvard Bioscience, Inc. Employee Stock Purchase Plan.

    **23.1       Consent of Counsel (included in Exhibit 5.1 hereto).

      23.2       Consent of KPMG LLP.

    **24.1       Powers of Attorney.
</TABLE>


+        Incorporated by reference to the relevant exhibit to the Registrant's
         Annual Report on Form 10-K for the fiscal year ended December 31, 2000,
         as filed with the Commission.

*        Incorporated by reference to the relevant exhibit to the Registrant's
         Registration Statement on Form S-1 (File No. 333-45996), as amended, as
         filed with the Commission.

**       Previously filed.





<PAGE>


                                                                    EXHIBIT 23.2

                          INDEPENDENT AUDITOR'S CONSENT


The Board of Directors
Harvard Bioscience, Inc. and Subsidiaries:

We consent to the use of our reports incorporated herein by reference on Form 
S-8 of Harvard Bioscience, Inc.


/s/ KPMG LLP

Boston, Massachusetts
June 15, 2001