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                                                                     EXHIBIT 8.1
                                  PERKINS COIE
 
             A LAW PARTNERSHIP INCLUDING PROFESSIONAL CORPORATIONS
     1211 SOUTHWEST FIFTH AVENUE, SUITE 1500 - PORTLAND, OREGON 97204-3715
               TELEPHONE: 503 727-2000 - FACSIMILE: 503 727-2222
 
                                  May 13, 1998
 
Teekay Shipping Corporation
4th Floor, Euro Canadian Centre
Marlborough Street & Navy Lion Road
P.O. Box SS-6293
Nassau, Commonwealth of the Bahamas
 
                     RE: REGISTRATION STATEMENT ON FORM F-3
 
Dear Sirs:
 
     We have acted as special United States tax counsel to Teekay Shipping
Corporation, a Liberian corporation (the "Company"), in connection with the
Registration Statement on Form F-3 (the "Registration Statement") filed by the
Company under the Securities Act of 1933, as amended (the "Securities Act"), and
the rules and regulations promulgated thereunder (the "Rules") with the
Securities and Exchange Commission today in connection with a proposed
underwritten public offering of up to 8,050,000 shares of the Company's Common
Stock. You have asked us to render our opinion as to matters hereinafter set
forth. Capitalized terms used but not defined herein shall have the same meaning
as in the Registration Statement.
 
     In this connection, we have examined such certificates, agreements,
records, and other documents as we have deemed relevant and necessary as a basis
for this opinion. We have assumed, with your permission and without independent
investigation, (i) the genuineness of all signatures, the authenticity of all
documents submitted to us as originals, the conformity to original documents of
all documents submitted to us as photostatic or facsimile copies, and the
authenticity of the originals of such copies, (ii) the accuracy of the factual
representations made to us by officers and other representatives of the Company,
whether evidenced by certificates or otherwise, and (iii) that all actions
contemplated by the Registration Statement have been and will be carried out
only in the manner described therein.
 
     Based on the foregoing, we are of the opinion that the summary set forth
under the heading "Tax Considerations--United States Tax Considerations" in the
Prospectus forming a part of the Registration Statement is accurate in all
material respects and describes the material United States federal income tax
consequences expected to be relevant to prospective holders of the Common Stock
who have acquired the Common Stock as a capital asset, are U.S. Holders (as
defined below) and are not among particular categories of investors subject to
special treatment under certain United States federal income tax laws. As used
herein, the terms "U.S. Holder" means a beneficial owner of Common Stock who or
that is for U.S. federal income tax purposes (i) a citizen or individual
resident of the United States, (ii) a corporation or partnership created or
organized in or under the laws of the United States or any political subdivision
thereof, (iii) an estate, the income of which is subject to U.S. federal income
taxation regardless of its source, or (iv) a trust, if both (A) a U.S. court is
able to exercise primary supervision over the administration of the trust, and
(B) one or more of U.S. persons have the authority to control all substantial
decisions of the trust.
 
     This opinion is based on provisions of the United States Internal Revenue
Code of 1986, as
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amended, applicable United States Treasury Department Regulations thereunder and
published administrative positions and judicial decisions thereof, all as of the
date hereof.
 
     In giving the opinion expressed herein, we express no opinion as to the
laws of any jurisdiction other than the federal income tax laws of the United
States.
 
     We consent to the filing of this opinion as an exhibit to the Registration
Statement and to the references to our firm in the Prospectus made part of the
Registration Statement under the "Tax Considerations--United States Tax
Considerations" and "Legal Matters". In giving such consent, we do not hereby
admit that we are in the category of persons whose consent is required under
Section 7 of the Securities Act or related Rules. This Consent may be
incorporated by reference in any amendment to the Registration Statement filed
pursuant to Rule 462(b) of Regulation C under the Securities Act.
 
                                            Very truly yours,
 
                                                     /s/  PERKINS COIE
 
                                            ------------------------------------
                                                        Perkins Coie
 
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