EXHIBIT 5.1

               [LETTERHEAD OF BALLARD SPAHR ANDREWS & INGERSOLL]



                                 April 23, 1998


Health Care Property Investors, Inc.
10990 Wilshire Boulevard
Suite 1200
Los Angeles, California 90024

          Re:  Health Care Property Investors, Inc., a Maryland corporation (the
               "Company") - up to Six Hundred Ninety-Eight Thousand Seven
               Hundred Fifty-Two (698,752) shares (the "Shares") of the Common
               Stock of the Company, par value $1.00 per share (the "Common
               Stock"), to be issued and sold pursuant to Registration Statement
               on Form S-3, as amended (Registration No. 333-29485), including
               the Prospectus dated September 19, 1997, comprising a part
               thereof (the "Prospectus"), and the Prospectus Supplement, dated
               April 23, 1998 (the "Prospectus Supplement")
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Ladies and Gentlemen:

          In connection with the registration of the offering and sale of the
Shares under the Securities Act of 1933, as amended (the "Act"), by the Company
on Form S-3 filed with the Securities and Exchange Commission on or about June
18, 1997, as amended, (the "Registration Statement"), you have requested our
opinion with respect to the matters set forth below.

          We have acted as special Maryland corporate counsel for the Company in
connection with the matters described herein.  In our capacity as special
Maryland corporate counsel to the Company, we have reviewed and are familiar
with proceedings proposed to be taken by the Company in connection with the
authorization, issuance and sale of the Shares, and for purposes of this opinion
have assumed such proceedings will be timely completed in the manner presently
proposed.  In addition, we have relied upon certificates and advice from the
officers of the Company upon which we believe we are justified in relying and on
various certificates from, and documents recorded with, the State Department of
Assessments and Taxation of Maryland (the "SDAT"), 

 
BALLARD SPAHR ANDREWS & INGERSOLL

Health Care Property Investors, Inc.
April 23, 1998
Page 2

including the charter of the Company (the "Charter"), consisting of Articles of
Restatement filed with the SDAT on April 27, 1992 and Articles Supplementary
filed with the SDAT on or about September 26, 1997. We have also examined the
Bylaws of the Company, as amended through the date hereof (the "Bylaws"), and
resolutions of the Board of Directors of the Company and committees thereof
adopted on or before the date hereof and in full force and effect on the date
hereof; and such laws, records, documents, certificates, opinions and
instruments as we deem necessary to render this opinion.

          We have assumed the genuineness of all signatures, the authenticity of
all documents submitted to us as originals and the conformity to the originals
of all documents submitted to us as certified, photostatic or conformed copies.
In addition, we have assumed that each person executing any instrument, document
or certificate referred to herein on behalf of any party is duly authorized to
do so.  We have also assumed that none of the Shares will be issued or
transferred in violation of the restrictions on ownership and transfer of stock
contained in the Charter of the Company and described in the Prospectus under
the caption "Transfer Restrictions, Redemption and Business Combination
Provisions".

          Based on the foregoing, and subject to the assumptions and
qualifications set forth herein, it is our opinion that, as of the date of this
letter, the Shares have been duly authorized by all necessary corporate action
on the part of the Company, and the Shares will, upon issuance and delivery in
accordance with the terms and conditions described in the Registration Statement
against payment of the purchase price therefor as determined by the Board of
Directors of the Company or a committee thereof, be validly issued, fully paid
and nonassessable.

          We consent to your filing this opinion as an exhibit to the
Registration Statement, and further consent to the filing of this opinion as an
exhibit to the applications to securities commissioners for the various states
of the United States for registration of the Shares.  We also consent to the
identification of our firm as Maryland counsel to the Company in the section of
the Prospectus (which is part of the Registration Statement) entitled "Legal
Matters."

 
BALLARD SPAHR ANDREWS & INGERSOLL

Health Care Property Investors, Inc.
April 23, 1998
Page 3

          The opinions expressed herein are limited to the laws of the State of
Maryland and we express no opinion concerning any laws other than the laws of
the State of Maryland.  Furthermore, the opinions presented in this letter are
limited to the matters specifically set forth herein and no other opinion shall
be inferred beyond the matters expressly stated.


                            Very truly yours,
 
                            /s/ Ballard Spahr Andrews & Ingersoll