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                                                                    Exhibit 5.1

                         [Letterhead of Venable LLP]

                                  December 7, 2004


Five Star Quality Care, Inc.
400 Centre Street
Newton, Massachusetts 02458

   Re:  REGISTRATION STATEMENT ON FORM S-1

Ladies and Gentlemen:

   We have served as Maryland counsel to Five Star Quality Care, Inc., a
Maryland corporation (the "Company"), in connection with certain matters of
Maryland law arising out of the registration of up to 4,025,000 shares (the
"Shares") of Common Stock, $.01 par value per share, of the Company (the
"Common Stock"), to be issued by the Company in an underwritten public
offering, covered by the above-referenced Registration Statement, and all
amendments thereto (the "Registration Statement"), filed by the Company with
the United States Securities and Exchange Commission (the "Commission") under
the Securities Act of 1933, as amended (the "1933 Act").  Unless otherwise
defined herein, capitalized terms used herein shall have the meanings
assigned to them in the Registration Statement.

   In connection with our representation of the Company, and as a basis for
the opinion hereinafter set forth, we have examined originals, or copies
certified or otherwise identified to our satisfaction, of the following
documents (hereinafter collectively referred to as the "Documents"):

   1. The Registration Statement and the related form of prospectus included
therein in the form in which it was transmitted to the Commission under the
1933 Act;

   2. The charter of the Company (the "Charter"), certified as of a recent
date by the State Department of Assessments and Taxation of Maryland (the
"SDAT");

   3. The Amended and Restated Bylaws of the Company, certified as of the
date hereof by an officer of the Company;

   4. A certificate of the SDAT as to the good standing of the Company, dated
as of a recent date;

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December 7, 2004
Page 2


   5. Resolutions adopted by the Board of Directors of the Company (the
"Board") relating to, among other matters, (a) the authorization and filing
of the Registration Statement and (b) the sale, issuance and registration of
the Shares (the "Resolutions"), certified as of the date hereof by an officer
of the Company;

   6. A certificate executed by an officer of the Company, dated as of the
date hereof; and

   7. Such other documents and matters as we have deemed necessary or
appropriate to express the opinion set forth below, subject to the
assumptions, limitations and qualifications stated herein.

   In expressing the opinion set forth below, we have assumed the following:

   1. Each individual executing any of the Documents, whether on behalf of
such individual or any other person, is legally competent to do so.

   2. Each individual executing any of the Documents on behalf of a party
(other than the Company) is duly authorized to do so.

   3. Each of the parties (other than the Company) executing any of the
Documents has duly and validly executed and delivered each of the Documents
to which such party is a signatory, and such party's obligations set forth
therein are legal, valid and binding and are enforceable in accordance with
all stated terms.

   4. All Documents submitted to us as originals are authentic.  The form and
content of all Documents submitted to us as unexecuted drafts do not differ
in any respect relevant to this opinion from the form and content of such
Documents as executed and delivered. All Documents submitted to us as
certified or photostatic copies conform to the original documents.  All
signatures on all such Documents are genuine.  All public records reviewed or
relied upon by us or on our behalf are true and complete.  All
representations, warranties, statements and information contained in the
Documents are true and complete.  There has been no oral or written
modification of or amendment to any of the Documents, and there has been no
waiver of any provision of any of the Documents, by action or omission of the
parties or otherwise.

   5. The Shares will not be issued in violation of any restriction or
limitation contained in Article VI (Restriction on Transfer and Ownership of
Shares) of the Charter.

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December 7, 2004
Page 3


   Based upon the foregoing, and subject to the assumptions, limitations and
qualifications stated herein, it is our opinion that:

   1. The Company is a corporation duly incorporated and existing under and
by virtue of the laws of the State of Maryland and is in good standing with
the SDAT.

   2. The issuance of the Shares has been duly authorized and, when and to
the extent issued in accordance with the Charter, the Registration Statement,
the Resolutions and any other resolutions adopted by the Board relating to
the Shares, the Shares will be (assuming that, upon issuance, the total
number of shares of Common Stock issued and outstanding will not exceed the
total number of shares of Common Stock that the Company is then authorized to
issue under the Charter) validly issued, fully paid and nonassessable.

   The foregoing opinion is limited to the laws of the State of Maryland and
we do not express any opinion herein concerning any other law.  We express no
opinion as to compliance with any federal or state securities laws, including
the securities laws of the State of Maryland, or as to federal or state laws
regarding fraudulent transfers.  To the extent that any matter as to which
our opinion is expressed herein would be governed by any jurisdiction other
than the State of Maryland, we do not express any opinion on such matter.
The opinion expressed herein is subject to the effect of judicial decisions
which may permit the introduction of parol evidence to modify the terms or
the interpretation of agreements.

   The opinion expressed herein is limited to the matters specifically set
forth herein and no other opinion shall be inferred beyond the matters
expressly stated.  We assume no obligation to supplement this opinion if any
applicable law changes after the date hereof or if we become aware of any
fact that might change the opinion expressed herein after the date hereof.

   This opinion is being furnished to you for submission to the Commission as
an exhibit to the Registration Statement.  We hereby consent to the filing of
this opinion as an exhibit to the Registration Statement and to the use of
the name of our firm therein in the section entitled "Legal matters" in the
Registration Statement.  In giving this consent, we do not admit that we are
within the category of persons whose consent is required by Section 7 of the
1933 Act.


                                                   Very truly yours,

                                                   /s/ Venable LLP