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                                                                     EXHIBIT 8.1



                                    January 16, 2003



Hospitality Properties Trust
400 Centre Street
Newton, Massachusetts  02458

Ladies and Gentlemen:

     In connection with the registration by Hospitality Properties Trust, a
Maryland real estate investment trust (the "Company"), of $175,000,000 of its
6.75% Senior Notes due February 15, 2013, the following opinion is furnished to
you to be filed with the Securities and Exchange Commission (the "SEC") as
Exhibit 8.1 to the Company's Current Report on Form 8-K to be filed within one
week of the date hereof, under the Securities Exchange Act of 1934, as amended
(the "Exchange Act").

     We have acted as counsel for the Company in connection with its
Registration Statements on Forms S-3, File No. 333-43573 and File No. 333-84064
(the "Registration Statements"), under the Securities Act of 1933, as amended
(the "Act"), and we have reviewed originals or copies, certified or otherwise
identified to our satisfaction, of the Registration Statements, corporate
records, certificates and statements of officers and accountants of the Company
and of public officials, and such other documents as we have considered relevant
and necessary in order to furnish the opinion hereinafter set forth.
Specifically, and without limiting the generality of the foregoing, we have
reviewed: (i) the Company's declaration of trust, as amended and restated, and
the by-laws of the Company, as amended and restated; (ii) the prospectus
supplement dated January 16, 2003 (the "Prospectus Supplement") to the final
prospectus dated March 20, 2002 (as supplemented by the Prospectus Supplement,
the "Prospectus") which forms a part of the Registration Statements; and (iii)
the sections in the Company's Form 10-K for the year ended December 31, 2001
captioned "Federal Income Tax Considerations" and "ERISA Plans, Keogh Plans and
Individual Retirement Accounts." With respect to all questions of fact on which
the opinion set forth below is based, we have assumed the accuracy and
completeness of and have relied on the information set forth in the Prospectus
and the Form 10-K and in the


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Hospitality Properties Trust
January 16, 2003
Page 2

documents incorporated therein by reference, and on representations made to us
by officers of the Company. We have not independently verified such information.

     The opinion set forth below is based upon the Internal Revenue Code of
1986, as amended, the Treasury Regulations issued thereunder, published
administrative interpretations thereof, and judicial decisions with respect
thereto, all as of the date hereof (collectively, the "Tax Laws"), and upon the
Employee Retirement Income Security Act of 1974, as amended, the Department of
Labor regulations issued thereunder, published administrative interpretations
thereof, and judicial decisions with respect thereto, all as of the date hereof
(collectively, the "ERISA Laws"). No assurance can be given that the Tax Laws or
the ERISA Laws will not change. In preparing the discussions with respect to Tax
Laws and ERISA Laws matters in the sections of the Form 10-K captioned "Federal
Income Tax Considerations" and "ERISA Plans, Keogh Plans and Individual
Retirement Accounts," we have made certain assumptions and expressed certain
conditions and qualifications therein, all of which assumptions, conditions and
qualifications are incorporated herein by reference. With respect to all
questions of fact on which our opinion is based, we have assumed the initial and
continuing truth, accuracy and completeness of: (i) the information set forth in
the Form 10-K, the Prospectus, and in the documents incorporated therein by
reference; and (ii) representations made to us by officers of the Company or
contained in the Form 10-K or the Prospectus in each such instance without
regard to qualifications such as "to the best knowledge of" or "in the belief
of".

     We have relied upon, but not independently verified, the foregoing
assumptions. If any of the foregoing assumptions are inaccurate or incomplete
for any reason, or if the transactions described in the Form 10-K or the
Prospectus (or the documents incorporated in either by reference) have been
consummated in a manner that is inconsistent with the manner contemplated
therein, our opinion as expressed below may be adversely affected and may not be
relied upon.

     Based upon and subject to the foregoing, we are of the opinion that the
discussions with respect to Tax Laws and ERISA Laws matters in the sections of
the Form 10-K captioned "Federal Income Tax Considerations" and "ERISA Plans,
Keogh Plans and Individual Retirement Accounts," as supplemented by the
discussion in the Prospectus Supplement captioned "Material Federal Income Tax
Considerations," in all material respects are accurate and fairly summarize the
Tax Laws issues and the ERISA Laws issues addressed therein, and hereby confirm
that the opinions of counsel referred to in said sections represent our opinions
on the subject matter thereof.

     Our opinion above is limited to the matters specifically covered hereby,
and we have not been asked to address, nor have we addressed, any other matters
or any other transactions. Further, we disclaim any undertaking to advise you of
any subsequent changes of the matters stated, represented or assumed herein or
any subsequent changes in the Tax Laws or the ERISA Laws.

     This opinion is intended solely for the benefit and use of the Company, and
is not to be used, released, quoted, or relied upon by anyone else for any
purpose (other than as required by


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Hospitality Properties Trust
January 16, 2003
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law) without our prior written consent. We hereby consent to filing of a copy of
this opinion as an exhibit to the Form 8-K, which is incorporated by reference
in the Company's Registration Statements under the Act, and to the references to
our firm in the Form 10-K and the Registration Statements. In giving such
consent, we do not thereby admit that we come within the category of persons
whose consent is required under Section 7 of the Act or under the rules and
regulations of the SEC promulgated thereunder.


                                      Very truly yours,

                                      /s/ Sullivan & Worcester LLP
                                      --------------------------------
                                      SULLIVAN & WORCESTER LLP




