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                                                                     EXHIBIT 5.1

                      LETTERHEAD OF CLIFFORD CHANCE US LLP

March 14, 2003


iStar Financial Inc.
1114 Avenue of the Americas, 27th Floor
New York, New York 10036

Dear Sirs:

     We have acted as counsel to iStar Financial Inc., a Maryland corporation
(the "Company"), in connection with the offer and sale by the Company of $150
million aggregate principal amount of its 7.0% Senior Notes due 2008 (the
"Securities"). The Securities are being sold pursuant to iStar Financial's
Registration Statement on Form S-3 (numbers 333-83646) under the Securities Act
of 1933, as amended (the "Registration Statements").

     Based on the foregoing, and such other examination of law and fact as we
have deemed necessary, we are of the opinion that the Securities have been
duly authorized by the Company and, when issued and sold in the manner
contemplated by the prospectus supplement for the offering of the Securities
dated March 11, 2003, the Securities will be legal, valid and binding
obligations of the Company.

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

Very truly yours,

/s/  CLIFFORD CHANCE US LLP