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                                                                   EXHIBIT 5.1




                                  [LETTERHEAD]


March 13, 1997




COULTER PHARMACEUTICAL, INC.
550 CALIFORNIA AVENUE, SUITE 200
PALO ALTO, CA  94306-1440


Ladies and Gentlemen:

You have requested our opinion with respect to certain matters in connection
with the filing by Coulter Pharmaceutical, Inc. (the "Company") of a
Registration Statement on Form S-8 (the "Registration Statement") with the
Securities and Exchange Commission covering the offering of 2,571,471 shares
the Company's Common Stock, $.001 par value, (the "Shares") with respect to (a)
1,730,000 of the Shares issuable pursuant to its 1996 Equity Incentive Plan and
Employee Stock Purchase Plan and (b) 841,471 of the Shares issuable pursuant to
outstanding options granted pursuant to its 1995 Equity Incentive Plan and 1996
Equity Incentive Plan (collectively, "the Plans").

In connection with this opinion, we have examined the Registration Statement
and related prospectus, your Certificate of Incorporation and Bylaws, as
amended, and such other documents, records, certificates, memoranda and other
instruments as we deem necessary as a basis for this opinion.  We have assumed
the genuineness and authenticity of all documents submitted to us as originals,
the conformity to originals of all documents submitted to us as copies thereof,
and the due execution and delivery of all documents where due execution and
delivery are a prerequisite to the effectiveness thereof.

On the basis of the foregoing, and in reliance thereon, we are of the opinion
that the Shares, when sold and issued in accordance with the Plans, the
Registration Statement and related prospectus, will be validly issued, fully
paid, and nonassessable (except as to shares issued pursuant to certain
deferred payment arrangements, which will be fully paid and nonassessable when
such deferred payments are made in full).

We consent to the filing of this opinion as an exhibit to the Registration
Statement.

Very truly yours,

Cooley Godward LLP


By: /s/ James C. Kitch
    ---------------------
        James C. Kitch