<PAGE>
 
             As filed with the Securities and Exchange Commission
                              on January 7, 1999

                                         Registration No. ______________________

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

                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                                   FORM S-8

                         REGISTRATION STATEMENT UNDER
                          THE SECURITIES ACT OF 1933

                       PARAMETRIC TECHNOLOGY CORPORATION
                    ---------------------------------------
            (Exact name of registrant as specified in its charter)



         Massachusetts                                        04-2866152
---------------------------------                           ------------------
(State or other jurisdiction of                              (I.R.S. Employer
incorporation or organization)                               Identification No.)



                    128 Technology Drive, Waltham, MA 02543
                   (Address of Principal Executive Offices)



                              INPART DESIGN, INC.
                           1997 STOCK INCENTIVE PLAN
                           -------------------------

                             (Full title of Plan)

                                Edwin J. Gillis
                           Executive Vice President
                       Parametric Technology Corporation
                             128 Technology Drive

                         Waltham, Massachusetts 02453
                         ----------------------------
                    (Name and address of agent for service)

                                (781) 398-5000
                                --------------
         (Telephone number, including area code, of agent for service)


                        CALCULATION OF REGISTRATION FEE
                        -------------------------------



<TABLE> 
<CAPTION> 
                                                          
                                                           
                                                Proposed                 Proposed               
Title of securities        Amount to be         maximum offering         maximum aggregate        Amount of 
to be registered           registered(1)        price per share(2)       offering price(2)        registration fee
----------------           -------------        ------------------       -----------------        ---------------- 
                 
<S>                      <C>                  <C>                      <C>                          <C> 

Common Stock,              148,873              $.15                      $22,331                       $7
$.01 par value             194,394              $.69                     $134,132                      $38

</TABLE> 

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

(1)  This Registration Statement registers shares to be offered by Registrant to
former employees of InPart Design, Inc. in connection with the acquisition of
InPart Design, Inc. by Registrant.

(2)  Estimated solely for the purpose of calculating the registration fee in
accordance with Rule 457(h) under the Securities Act of 1933, as amended, and
based on the price at which the options may be exercised.
<PAGE>
 
PART I.  INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS


          The information required by Part I of Form S-8 is included in
documents sent or given to participants in the InPart Design, Inc. 1997 Stock
Incentive Plan by Parametric Technology Corporation, a Massachusetts corporation
(the "Registrant" or "PTC"), pursuant to Rule 428(b)(1) of the Securities Act of
1933, as amended (the "Securities Act").


PART II.  INFORMATION REQUIRED IN THE REGISTRATION STATEMENT


Item 3.  Incorporation of Documents by Reference.
-------------------------------------------------


     The following documents filed with the Securities and Exchange Commission
(the "Commission") are incorporated herein by reference:


     (a)  The Registrant's latest annual report on Form 10-K filed pursuant
to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended
(the "Exchange Act").

     (b)   All other reports of the Registrant 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.

     (c)    The description of the Registrant's Common Stock, par value $.01
per share (the "Common Stock"), contained in the Registrant's registration
statement on Form 8-A, filed with the Commission October 26, 1989, under the
Exchange Act, including any amendment or report filed for the purpose of
updating such description.

     All documents filed after the date of this Registration Statement by the
Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act
and prior to the filing of a post-effective amendment that indicates that all
shares of Common Stock offered hereunder have been sold or which deregisters all
shares of Common Stock remaining unsold shall be deemed to be incorporated by
reference herein and to be a part hereof from the date of the filing of such
reports and 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 in any other subsequently filed document which
also is or is deemed to be 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.


Item 4.  Description of Securities.
-----------------------------------

     Not applicable.


Item 5.  Interests of Named Experts and Counsel.
------------------------------------------------

     Not applicable.


Item 6.  Indemnification of Directors and Officers.
---------------------------------------------------


     Section 67 of Chapter 156B of the Massachusetts Business Corporation Law
grants PTC the power to indemnify any director, officer, employee or agent to
whatever extent permitted by PTC's Articles of Organization, By-Laws or a vote
adopted by the holders of a majority of the shares entitled to vote thereon,
unless the proposed indemnitee has been adjudicated in any proceeding not to
have acted in good faith in the reasonable belief that his 

                                       2
<PAGE>
 
action was in the best interests of PTC or, to the extent that the matter for
which indemnification is sought relates to service with respect to an employee
benefit plan, in the best interests of the participants or beneficiaries of such
employee benefit plan. Such indemnification may include payment by PTC of
expenses incurred in defending a civil or criminal action or proceeding in
advance of the final disposition of such action or proceeding, upon receipt of
an undertaking by the person indemnified to repay such payment if he shall be
adjudicated to be not entitled to indemnification under the statute.


     Article 6B of PTC's Articles of Organization provides that PTC shall, to
the fullest extent legally permissible, indemnify each person at any time
elected or appointed a director or officer of PTC, or who serves at PTC's
request as a director or officer of another organization or in any capacity with
respect to any employee benefit plan against any and all costs and expenses
(including but not limited to court costs and legal fees) reasonably incurred
by, and any and all liabilities imposed upon, him in connection with, or arising
out of, or resulting from, any claim made, or any action, suit or proceeding
(whether civil, criminal, administrative or investigative) threatened or
brought, against him or in which he may be involved as a party or otherwise by
reason of his having so served or by reason of any action taken or omitted or
alleged to have been taken or omitted by him in such capacity unless in any
proceeding such person shall have been finally adjudicated with respect to the
matter or matters as to which indemnification is sought not to have acted in
good faith in the reasonable belief that his action was in the best interest of
PTC or, to the extent that such matter or matters relate to service with respect
to an employee benefit plan, in the best interests of the participants or
beneficiaries of such employee benefit plan. Such indemnification shall include
payment by PTC of expenses incurred in defending any such action, suit or
proceeding in advance of the final disposition of such action, suit or
proceeding, upon receipt of an undertaking by or on behalf of the person
indemnified to repay such payment if he shall be adjudicated to be not entitled
to indemnification under Article VI, which undertaking shall be accepted without
reference to the financial ability of such person to make repayment.

     The right of indemnification under Article 6B does not extend to amounts
incurred or paid in connection with any matter which shall be disposed of
through a compromise payment or other settlement prior to final adjudication,
whether by or pursuant to a consent decree or otherwise, unless such compromise
or other settlement is approved by PTC, which approval shall not unreasonably be
withheld, or by a court of competent jurisdiction. Article VI sets forth certain
circumstances under which the payment of indemnification is conclusively deemed
approved by PTC. Article VI also contains certain procedural and other
provisions which provide additional protection for persons seeking
indemnification.

     The indemnification provided for in Article VI is a contract right inuring
to the benefit of the directors, officers and others entitled to
indemnification. In addition, the indemnification is expressly in addition to
and not exclusive of any other rights to which such director, officer or other
person may be entitled and inures to the benefit of the heirs, executors,
administrators and legal representatives of such a person.

     Section 13(b)(1 1/2) of Chapter 156B of the Massachusetts Business
Corporation Law provides that a corporation may, in its Articles of
Organization, eliminate the directors' personal liability to the corporation and
its stockholders for monetary damages for breaches of fiduciary duty, except in
circumstances involving (i) a breach of the director's duty of loyalty to the
corporation or its stockholders, (ii) acts or omissions not in good faith or
which involve intentional misconduct or a knowing violation of law, (iii)
unauthorized distributions and loans to insiders, and (iv) transactions from
which the director derived an improper personal benefit. PTC's Articles of
Organization include a provision providing that no director shall be personally
liable to PTC or its stockholders for monetary damages for any breach of
fiduciary duty as a director, except to the extent that such exculpation is not
permitted under the provisions of the Massachusetts Business Corporation Law
summarized above. No amendment or repeal of that provision of the Articles of
Organization shall apply or have any effect on the liability of any director for
or with respect to acts or omissions occurring prior to the amendment or repeal.

                                       3
<PAGE>
 
     PTC maintains an insurance policy on behalf of the directors and officers
of PTC and its subsidiaries covering certain liabilities which may arise as a
result of the actions of said directors and officers.


The provisions described above may be sufficiently broad to indemnify directors
and officers and control persons of PTC against liability arising under the
Securities Act of 1933, as amended (the "Act"). Insofar as indemnification for
liabilities arising under the Act may be permitted to directors, officers or
persons controlling PTC pursuant to the foregoing provisions, PTC has been
informed that, in the opinion of the Securities and Exchange Commission, such
indemnification is against public policy as expressed in the Act and is
therefore unenforceable.


Item 7. Exemption from Registration Claimed.
--------------------------------------------

  Not applicable.


Item 8.  Exhibits.
------------------

  See Exhibit Index immediately following signature pages.


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 Commission pursuant to Rule 424(b) if, in the aggregate, the
changes in volume and price represent no more than 20 percent change in the
maximum aggregate offering price set forth in the "Calculation of Registration
Fee" table in the effective registration statement.

          (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
registration statement is on Form S-3, Form S-8 or Form F-3, and 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 Commission by the
Registrant pursuant to Section 13 of 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 

                                       4
<PAGE>
 
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.

   (b) 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 any
employee benefit plan's annual report pursuant to Section 15(d) of the
Securities Act of 1934) that is incorporated by reference in this 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 of 1933 may be permitted to directors, officers and controlling persons of
the Registrant pursuant to the provisions referred to in Item 6 hereof, 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 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 Act and will
be governed by the final adjudication of such issue.

                                       5
<PAGE>
 
                                   SIGNATURES
                                   ----------


  Pursuant to the requirements of the Securities Act, 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 Waltham, Massachusetts, on the 5th day of January, 1999.

  PARAMETRIC TECHNOLOGY CORPORATION



                                    By:   /s/ Edwin J. Gillis        
                                         --------------------                
                                         Edwin J. Gillis
                                         Executive Vice President,
                                         Chief Financial Officer and Treasurer



                               POWER OF ATTORNEY
                               -----------------


          We, the undersigned officers and directors of Parametric Technology
Corporation, hereby severally constitute Edwin J. Gillis and David Friedman,
Esq., and each of them singly, our true and lawful attorneys with full power to
them, and each of them singly, to sign for us and in our names in the capacities
indicated below, the Registration Statement on Form S-8 filed herewith and any
and all subsequent amendments to said Registration Statement, and generally to
do all such things in our names and behalf in our capacities as officers and
directors to enable Parametric Technology Corporation to comply with all
requirements of the Securities and Exchange Commission, hereby ratifying and
confirming our signatures as they may be signed by said attorneys, or any of
them, to said Registration Statement and any and all amendments thereto.

          WITNESS our hands and common seal on the date set forth below.

          Pursuant to the requirements of the Securities Act, this Registration
Statement has been signed below by the following persons in the capacities and
on the dates indicated.

<TABLE> 
<CAPTION> 

     Signature                           Title                      Date
     ---------                           -----                      ----

<S>                               <C>                         <C>    
(i)  Principal Executive Officer:



      /s/ Steven C. Walske         Chief Executive Officer      October 19, 1998 
     ---------------------         and Chairman of the Board                 
     Steven C. Walske                                            

(ii) Principal Financial and
     Accounting Officer:


      /s/ Edwin J. Gillis          Executive Vice President,    January 5, 1999 
     --------------------          Chief Financial Officer   
     Edwin J. Gillis               and Treasurer     

                                      
</TABLE> 

                                       6
<PAGE>
 
<TABLE> 
<CAPTION> 

     Signature                           Title               Date
     ---------                           -----               ----
<S>                                  <C>                  <C> 

(iii)  Board of Directors:



      /s/ Steven C. Walske               Director          October 19, 1998
     ---------------------                                                 
     Steven C. Walske



      /s/ C. Richard Harrison            Director          October 14, 1998
     ------------------------                                              
     C. Richard Harrison



     /s/ Robert N. Goldman               Director          October 14, 1998
     ---------------------                                                 
     Robert N. Goldman



      /s/ Donald K. Grierson             Director          October 12, 1998
     -----------------------                                               
     Donald K. Grierson



      /s/ Oscar B. Marx, III             Director          October 9, 1998
     -----------------------                                              
     Oscar B. Marx, III



      /s/ Michael E. Porter              Director          October 8, 1998
     ----------------------                                               
     Michael E. Porter



      /s/ Noel G. Posternak              Director          October 9, 1998
     ----------------------                                               
     Noel G. Posternak

</TABLE> 

                                       7
<PAGE>
 
                                 EXHIBIT INDEX



Exhibit
Number        Description
------        -----------



4.1(a)*       Restated Articles of Organization (incorporated herein by
              reference to Exhibit 3.1 to Registrant's Quarterly Report on Form
              10-Q, filed on May 14, 1996).



4.1(b)*       Articles of Amendment to Restated Articles of Organization
              (incorporated herein by reference to Exhibit 4.1(b) of
              Registrant's Registration Statement on Form S-8, filed on 
              February 21, 1997).



4.2*          By-Laws of the Registrant, as amended and restated (incorporated
              herein by reference to Exhibit 3.2 to Registrant's Annual Report
              on Form 10-K, filed on December 24, 1996).


5.1           Opinion of Palmer & Dodge LLP as to the legality of the securities
              registered hereunder.

23.1          Consent of Palmer & Dodge LLP (included in Exhibit 5.1).


23.2          Consent of PricewaterhouseCoopers LLP.


23.3          Consent of Arthur Andersen LLP.


24.1          Power of Attorney (contained on the signature page hereto).



 
-------------------------------
* Incorporated by reference
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 22670}]
{"company-data": {"conformed-name": "PARAMETRIC TECHNOLOGY CORP", "cik": "0000857005", "assigned-sic": "7372", "irs-number": "042866152", "state-of-incorporation": "MA", "fiscal-year-end": "0930"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-70227", "film-number": "99502306"}, "business-address": {"street1": "128 TECHNOLOGY DR", "city": "WALTHAM", "state": "MA", "zip": "02154", "phone": "7813985000"}, "mail-address": {"street1": "128 TECHNOLOGY CORP", "city": "WALTHAM", "state": "MA", "zip": "02154"}}
As filed with the Securities and Exchange Commission
                              on January 7, 1999

                                         Registration No. ______________________

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

                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                                   FORM S-8

                         REGISTRATION STATEMENT UNDER
                          THE SECURITIES ACT OF 1933

                       PARAMETRIC TECHNOLOGY CORPORATION
                    ---------------------------------------
            (Exact name of registrant as specified in its charter)

         Massachusetts                                        04-2866152
---------------------------------                           ------------------
(State or other jurisdiction of                              (I.R.S. Employer
incorporation or organization)                               Identification No.)

                    128 Technology Drive, Waltham, MA 02543
                   (Address of Principal Executive Offices)

                              INPART DESIGN, INC.
                           1997 STOCK INCENTIVE PLAN
                           -------------------------

                             (Full title of Plan)

                                Edwin J. Gillis
                           Executive Vice President
                       Parametric Technology Corporation
                             128 Technology Drive

                         Waltham, Massachusetts 02453
                         ----------------------------
                    (Name and address of agent for service)

                                (781) 398-5000
                                --------------
         (Telephone number, including area code, of agent for service)

                        CALCULATION OF REGISTRATION FEE
                        -------------------------------
Proposed                 Proposed               
Title of securities        Amount to be         maximum offering         maximum aggregate        Amount of 
to be registered           registered(1)        price per share(2)       offering price(2)        registration fee
----------------           -------------        ------------------       -----------------        ----------------
Common Stock,              148,873              $.15                      $22,331                       $7
$.01 par value             194,394              $.69                     $134,132                      $38
--------------------------------------------------------------------------------

(1)  This Registration Statement registers shares to be offered by Registrant to
former employees of InPart Design, Inc. in connection with the acquisition of
InPart Design, Inc. by Registrant.

(2)  Estimated solely for the purpose of calculating the registration fee in
accordance with Rule 457(h) under the Securities Act of 1933, as amended, and
based on the price at which the options may be exercised.
PART I.  INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

          The information required by Part I of Form S-8 is included in
documents sent or given to participants in the InPart Design, Inc. 1997 Stock
Incentive Plan by Parametric Technology Corporation, a Massachusetts corporation
(the "Registrant" or "PTC"), pursuant to Rule 428(b)(1) of the Securities Act of
1933, as amended (the "Securities Act").

PART II.  INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Documents by Reference.
-------------------------------------------------

     The following documents filed with the Securities and Exchange Commission
(the "Commission") are incorporated herein by reference:

     (a)  The Registrant's latest annual report on Form 10-K filed pursuant
to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended
(the "Exchange Act").

     (b)   All other reports of the Registrant 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.

     (c)    The description of the Registrant's Common Stock, par value $.01
per share (the "Common Stock"), contained in the Registrant's registration
statement on Form 8-A, filed with the Commission October 26, 1989, under the
Exchange Act, including any amendment or report filed for the purpose of
updating such description.

     All documents filed after the date of this Registration Statement by the
Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act
and prior to the filing of a post-effective amendment that indicates that all
shares of Common Stock offered hereunder have been sold or which deregisters all
shares of Common Stock remaining unsold shall be deemed to be incorporated by
reference herein and to be a part hereof from the date of the filing of such
reports and 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 in any other subsequently filed document which
also is or is deemed to be 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.

Item 4.  Description of Securities.
-----------------------------------

     Not applicable.

Item 5.  Interests of Named Experts and Counsel.
------------------------------------------------

     Not applicable.

Item 6.  Indemnification of Directors and Officers.
---------------------------------------------------

     Section 67 of Chapter 156B of the Massachusetts Business Corporation Law
grants PTC the power to indemnify any director, officer, employee or agent to
whatever extent permitted by PTC's Articles of Organization, By-Laws or a vote
adopted by the holders of a majority of the shares entitled to vote thereon,
unless the proposed indemnitee has been adjudicated in any proceeding not to
have acted in good faith in the reasonable belief that his 

                                       2
action was in the best interests of PTC or, to the extent that the matter for
which indemnification is sought relates to service with respect to an employee
benefit plan, in the best interests of the participants or beneficiaries of such
employee benefit plan. Such indemnification may include payment by PTC of
expenses incurred in defending a civil or criminal action or proceeding in
advance of the final disposition of such action or proceeding, upon receipt of
an undertaking by the person indemnified to repay such payment if he shall be
adjudicated to be not entitled to indemnification under the statute.

     Article 6B of PTC's Articles of Organization provides that PTC shall, to
the fullest extent legally permissible, indemnify each person at any time
elected or appointed a director or officer of PTC, or who serves at PTC's
request as a director or officer of another organization or in any capacity with
respect to any employee benefit plan against any and all costs and expenses
(including but not limited to court costs and legal fees) reasonably incurred
by, and any and all liabilities imposed upon, him in connection with, or arising
out of, or resulting from, any claim made, or any action, suit or proceeding
(whether civil, criminal, administrative or investigative) threatened or
brought, against him or in which he may be involved as a party or otherwise by
reason of his having so served or by reason of any action taken or omitted or
alleged to have been taken or omitted by him in such capacity unless in any
proceeding such person shall have been finally adjudicated with respect to the
matter or matters as to which indemnification is sought not to have acted in
good faith in the reasonable belief that his action was in the best interest of
PTC or, to the extent that such matter or matters relate to service with respect
to an employee benefit plan, in the best interests of the participants or
beneficiaries of such employee benefit plan. Such indemnification shall include
payment by PTC of expenses incurred in defending any such action, suit or
proceeding in advance of the final disposition of such action, suit or
proceeding, upon receipt of an undertaking by or on behalf of the person
indemnified to repay such payment if he shall be adjudicated to be not entitled
to indemnification under Article VI, which undertaking shall be accepted without
reference to the financial ability of such person to make repayment.

     The right of indemnification under Article 6B does not extend to amounts
incurred or paid in connection with any matter which shall be disposed of
through a compromise payment or other settlement prior to final adjudication,
whether by or pursuant to a consent decree or otherwise, unless such compromise
or other settlement is approved by PTC, which approval shall not unreasonably be
withheld, or by a court of competent jurisdiction. Article VI sets forth certain
circumstances under which the payment of indemnification is conclusively deemed
approved by PTC. Article VI also contains certain procedural and other
provisions which provide additional protection for persons seeking
indemnification.

     The indemnification provided for in Article VI is a contract right inuring
to the benefit of the directors, officers and others entitled to
indemnification. In addition, the indemnification is expressly in addition to
and not exclusive of any other rights to which such director, officer or other
person may be entitled and inures to the benefit of the heirs, executors,
administrators and legal representatives of such a person.

     Section 13(b)(1 1/2) of Chapter 156B of the Massachusetts Business
Corporation Law provides that a corporation may, in its Articles of
Organization, eliminate the directors' personal liability to the corporation and
its stockholders for monetary damages for breaches of fiduciary duty, except in
circumstances involving (i) a breach of the director's duty of loyalty to the
corporation or its stockholders, (ii) acts or omissions not in good faith or
which involve intentional misconduct or a knowing violation of law, (iii)
unauthorized distributions and loans to insiders, and (iv) transactions from
which the director derived an improper personal benefit. PTC's Articles of
Organization include a provision providing that no director shall be personally
liable to PTC or its stockholders for monetary damages for any breach of
fiduciary duty as a director, except to the extent that such exculpation is not
permitted under the provisions of the Massachusetts Business Corporation Law
summarized above. No amendment or repeal of that provision of the Articles of
Organization shall apply or have any effect on the liability of any director for
or with respect to acts or omissions occurring prior to the amendment or repeal.

                                       3
PTC maintains an insurance policy on behalf of the directors and officers
of PTC and its subsidiaries covering certain liabilities which may arise as a
result of the actions of said directors and officers.

The provisions described above may be sufficiently broad to indemnify directors
and officers and control persons of PTC against liability arising under the
Securities Act of 1933, as amended (the "Act"). Insofar as indemnification for
liabilities arising under the Act may be permitted to directors, officers or
persons controlling PTC pursuant to the foregoing provisions, PTC has been
informed that, in the opinion of the Securities and Exchange Commission, such
indemnification is against public policy as expressed in the Act and is
therefore unenforceable.

Item 7. Exemption from Registration Claimed.
--------------------------------------------

  Not applicable.

Item 8.  Exhibits.
------------------

  See Exhibit Index immediately following signature pages.

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 Commission pursuant to Rule 424(b) if, in the aggregate, the
changes in volume and price represent no more than 20 percent change in the
maximum aggregate offering price set forth in the "Calculation of Registration
Fee" table in the effective registration statement.

          (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
registration statement is on Form S-3, Form S-8 or Form F-3, and 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 Commission by the
Registrant pursuant to Section 13 of 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 

                                       4
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.

   (b) 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 any
employee benefit plan's annual report pursuant to Section 15(d) of the
Securities Act of 1934) that is incorporated by reference in this 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 of 1933 may be permitted to directors, officers and controlling persons of
the Registrant pursuant to the provisions referred to in Item 6 hereof, 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 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 Act and will
be governed by the final adjudication of such issue.

                                       5
SIGNATURES
                                   ----------

  Pursuant to the requirements of the Securities Act, 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 Waltham, Massachusetts, on the 5th day of January, 1999.

  PARAMETRIC TECHNOLOGY CORPORATION

                                    By:   /s/ Edwin J. Gillis        
                                         --------------------                
                                         Edwin J. Gillis
                                         Executive Vice President,
                                         Chief Financial Officer and Treasurer

                               POWER OF ATTORNEY
                               -----------------

          We, the undersigned officers and directors of Parametric Technology
Corporation, hereby severally constitute Edwin J. Gillis and David Friedman,
Esq., and each of them singly, our true and lawful attorneys with full power to
them, and each of them singly, to sign for us and in our names in the capacities
indicated below, the Registration Statement on Form S-8 filed herewith and any
and all subsequent amendments to said Registration Statement, and generally to
do all such things in our names and behalf in our capacities as officers and
directors to enable Parametric Technology Corporation to comply with all
requirements of the Securities and Exchange Commission, hereby ratifying and
confirming our signatures as they may be signed by said attorneys, or any of
them, to said Registration Statement and any and all amendments thereto.

          WITNESS our hands and common seal on the date set forth below.

          Pursuant to the requirements of the Securities Act, this Registration
Statement has been signed below by the following persons in the capacities and
on the dates indicated.
Signature                           Title                      Date
     ---------                           -----                      ----
(i)  Principal Executive Officer:

      /s/ Steven C. Walske         Chief Executive Officer      October 19, 1998 
     ---------------------         and Chairman of the Board                 
     Steven C. Walske                                            

(ii) Principal Financial and
     Accounting Officer:

      /s/ Edwin J. Gillis          Executive Vice President,    January 5, 1999 
     --------------------          Chief Financial Officer   
     Edwin J. Gillis               and Treasurer
6
Signature                           Title               Date
     ---------                           -----               ----
(iii)  Board of Directors:

      /s/ Steven C. Walske               Director          October 19, 1998
     ---------------------                                                 
     Steven C. Walske

      /s/ C. Richard Harrison            Director          October 14, 1998
     ------------------------                                              
     C. Richard Harrison

     /s/ Robert N. Goldman               Director          October 14, 1998
     ---------------------                                                 
     Robert N. Goldman

      /s/ Donald K. Grierson             Director          October 12, 1998
     -----------------------                                               
     Donald K. Grierson

      /s/ Oscar B. Marx, III             Director          October 9, 1998
     -----------------------                                              
     Oscar B. Marx, III

      /s/ Michael E. Porter              Director          October 8, 1998
     ----------------------                                               
     Michael E. Porter

      /s/ Noel G. Posternak              Director          October 9, 1998
     ----------------------                                               
     Noel G. Posternak
7
EXHIBIT INDEX

Exhibit
Number        Description
------        -----------

4.1(a)*       Restated Articles of Organization (incorporated herein by
              reference to Exhibit 3.1 to Registrant's Quarterly Report on Form
              10-Q, filed on May 14, 1996).

4.1(b)*       Articles of Amendment to Restated Articles of Organization
              (incorporated herein by reference to Exhibit 4.1(b) of
              Registrant's Registration Statement on Form S-8, filed on 
              February 21, 1997).

4.2*          By-Laws of the Registrant, as amended and restated (incorporated
              herein by reference to Exhibit 3.2 to Registrant's Annual Report
              on Form 10-K, filed on December 24, 1996).

5.1           Opinion of Palmer & Dodge LLP as to the legality of the securities
              registered hereunder.

23.1          Consent of Palmer & Dodge LLP (included in Exhibit 5.1).

23.2          Consent of PricewaterhouseCoopers LLP.

23.3          Consent of Arthur Andersen LLP.

24.1          Power of Attorney (contained on the signature page hereto).

 
-------------------------------
* Incorporated by reference