Exhibit 5.1

[Clifford Chance US LLP Letterhead]

Clifford Chance US LLP
200 Park Avenue
New York, New York 10166

TEL: +1 212 878 8000
FAX: +1 212 878 8375
www.cliffordchance.com

December 2, 2003

MFA Mortgage Investments, Inc.
350 Park Avenue, 21st Floor
New York, New York 10022

Re: Registration Statement on Form S-3 relating to 9,130,706 shares of
common stock issuable pursuant to the Discount Waiver, Direct Stock
Purchase and Dividend Reinvestment Plan (the "Plan") of MFA Mortgage
Investments, Inc.

Ladies and Gentlemen:

We have acted as counsel to MFA Mortgage Investments, Inc., a Maryland
corporation (the "Company"), in connection with the Company's registration
statement on Form S-3, as filed with the Securities and Exchange Commission (the
"Commission") on December 3, 2003 (the "Registration Statement") under the
Securities Act of 1933, as amended (the "Securities Act"), in connection with
the registration of 9,130,706 shares (the "Shares") of the Company's common
stock, par value $0.01 per share, which may be issued from time to time pursuant
to the Plan and which amends, pursuant to Rule 429 of the Securities Act, the
Company's prior registration statement on Form S-3 (File No. 333-83620).

In rendering this opinion, we have examined originals or copies, certified or
otherwise identified to our satisfaction, of such documents, corporate records,
certificates and other instruments as we have deemed necessary or appropriate
for the purposes of rendering this opinion. In such examination, we have assumed
the genuineness of all signatures, the authenticity of all documents,
certificates and instruments submitted to us as originals, the conformity with
originals of all documents submitted to us as copies and the absence of any
amendments or modifications to those items reviewed by us. As to any facts
material to this opinion which we have not independently established or
verified, we have relied upon statements and representations of representatives
of the Company and others.

Based upon the foregoing, and such other examination of law and fact as we have
deemed necessary, we are of the opinion that the Shares have been duly
authorized for issuance and, when the Shares are issued and delivered by the
Company upon receipt of the consideration therefor as provided in, and otherwise
in accordance with, the Plan and the resolutions of the Company's Board of
Directors authorizing the adoption of the Plan and the registration of the
Shares, the Shares will be legally issued, fully paid and non-assessable.

The opinion stated herein is limited to the Maryland General Corporation Law. We
do not express any opinion with respect to the law of any other jurisdiction or
as to the effect of any such law on the opinion herein stated.



We consent to the filing of this opinion as an exhibit to the Registration
Statement and to the reference to this firm under the caption "Legal Matters" in
the prospectus which is part of the Registration Statement.

Very truly yours,

/s/ CLIFFORD CHANCE US LLP