EXHIBIT 5.1

                               PALMER & DODGE LLP
                   111 Huntington Avenue at Prudential Center
                              Boston, MA 02199-7613


February 15, 2002


Parametric Technology Corporation
140 Kendrick Street
Needham, MA 02494

Ladies and Gentlemen:

We have assisted in the preparation of a Registration Statement on Form S-8 (the
"Registration Statement") to be filed with the Securities and Exchange
Commission relating to 4,000,000 shares of Common Stock, $.01 par value per
share (the "Shares"), of Parametric Technology Corporation, a Massachusetts
corporation (the "Company"), issuable upon exercise of options granted or to be
granted under the Company's 1997 Non Statutory Stock Option Plan (the "Plan").

It is our opinion that the Shares have been duly authorized for issuance and,
when issued in accordance with the terms of the Plan, will be legally issued,
fully paid and nonassessable.

We hereby consent to the use of our name in the Registration Statement and
consent to the filing of this opinion with the Securities and Exchange
Commission as an exhibit to the Registration Statement.

Very truly yours,


/s/ PALMER & DODGE LLP

PALMER & DODGE LLP











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