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Exhibit 5.1

     May 24, 2001

     Capital One Financial Corporation
     2980 Fairview Park Drive
     Falls Church, Virginia 22042-4525

     Ladies and Gentlemen:

     This opinion is furnished in connection with the filing by Capital One
Financial Corporation (the "Company") with the Securities and Exchange
Commission of a Registration Statement on Form S-3 (the "Registration
Statement") under the Securities Act of 1933, as amended. You have requested my
opinion concerning the status under Delaware law of the 257,201 shares (the
"Shares") of the Company's common stock, par value $.01 per share, and certain
Preferred Stock Purchase Rights which are being registered under the
Registration Statement for resale by certain of the Company's stockholders. All
Shares included in the Registration Statement have been issued and are
outstanding.

     I am General Counsel to the Company and I or attorneys under my supervision
have acted as counsel in connection with the Registration Statement. In that
connection, I, or an attorney under my supervision upon whom I have relied, have
examined and are familiar with originals or copies, certified or otherwise,
identified to our satisfaction, of:

     (1)  Amended Restated Certificate of Incorporation of the Company, as
          currently in effect;

     (2)  Restated By-Laws of the Company as currently in effect;

     (3)  Certain resolutions adopted by the Company's Board of Directors;

     (4)  Rights Agreement of the Company dated as of November 16, 1995, as
          amended; and

     (5)  the Registration Statement.

     In our examination, we have assumed the genuineness of all signatures, the
legal capacity of natural persons, the authenticity of all documents submitted
to us as originals, the conformity to original documents of all documents
submitted to us as certified or photostatic copies and the authenticity of the
originals of such copies.

     Based upon and subject to the foregoing, I am of the opinion that the
Shares and the related Preferred Stock Purchase Rights are duly authorized,
validly issued, fully-paid and non-assessable.

     You acknowledge that I am admitted to practice only in Virginia and am not
an expert in the laws of any other jurisdiction. No one other than the
addressees and their assigns are permitted to rely on or distribute this opinion
without the prior written consent of the undersigned.

     This opinion is limited to the General Corporation Law of the State of
Delaware and federal law, although the Company acknowledges that I am not
admitted to practice in the State of Delaware and am not an expert in the laws
of that jurisdiction. I express no opinion with respect to the laws of any other
jurisdiction.



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     I hereby consent to the filing of this opinion as an exhibit to the
Registration Statement, and further consent to the use of my name wherever
appearing in the Registration Statement and any amendment thereto.

                                    Very truly yours,

                                    /s/ John G. Finneran, Jr.
                                    -------------------------------------------
                                    John G. Finneran, Jr.
                                    Executive Vice President, General Counsel
                                       and Corporate Secretary


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