Exhibit 5.1

                                                February 14, 2001

Board of Directors
Priceline.com Incorporated
Five High Ridge Park
Stamford, Connecticut 06905

            Re: Priceline.com Incorporated Registration Statement on Form S-8

Ladies and Gentlemen:

      I am Vice President, Acting General Counsel and Assistant Secretary of
Priceline.com Incorporated, a Delaware corporation (the "Company"), and have
acted as counsel to the Company in connection with the registration under the
Securities Act of 1933, as amended (the "Securities Act"), of the shares of the
Company's Common stock, par value $0.008 per share (the "Common Stock"), to be
issued pursuant to or reserved for issuance under priceline.com's 1999 Omnibus
Plan, as amended, the priceline.com 2000 Employee Stock Option Plan and that
certain Agreement, dated November 20, 2000, by and between the Company and Mr.
Robert Mylod (together, the "Plans").

      This opinion is being furnished in accordance with the requirements of
Item 601(b)(5) of Regulation S-K under the Securities Act.

      In connection with this opinion, I have examined originals or copies,
certified or otherwise identified to my satisfaction, of (i) the Registration
Statement on Form S-8 to be filed with the Securities and Exchange Commission
(the "Commission") (such Registration Statement, as so amended or supplemented,
being hereinafter referred to as the "Registration Statement"); (ii) the Plans;
(iii) the Amended and Restated Certificate of Incorporation and the By-Laws of
the Company, each as currently in effect; and (iv) certain resolutions of the
Board of Directors of the Company relating to the approval and adoption of the
Plans, the issuance of the Common Stock and certain related matters. I also have
examined originals or copies, certified or otherwise identified to my
satisfaction, of such records of the Company and such agreements, certificates
of public officials, certificates of officers or other representatives of the
Company and others, and such other documents, certificates and records as I have
deemed necessary or appropriate as a basis for the opinions set forth herein.

      In my examination, I have assumed the legal capacity of all natural
persons, the genuineness of all signatures, the authenticity of all documents
submitted to me as originals, the conformity to original documents of all
documents submitted to me as certified, conformed or photostatic copies and the
authenticity of the originals of such latter documents. In making my examination
of executed documents, I have assumed that the parties thereto, other than the
Company, had the power, corporate or other, to enter into and perform all
obligations thereunder and have also assumed the due authorization by all
requisite action, corporate or other, and execution and delivery by such parties
of such documents and the validity and binding effect thereof on such parties.
As to any facts material to the opinions expressed herein which I have not
independently established or verified, I have relied upon statements and
representations of officers and other representatives of the Company and others.


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      I am admitted to the bar in the State of New York and I do not express any
opinion as to the laws of any other jurisdiction other than the General
Corporation Law of the State of Delaware, and I do not express any opinion as to
the effect of any other laws on the opinion stated herein.

      Based upon and subject to the foregoing, I am of the opinion that the
Company has the full power and authority under the General Corporation Law of
the State of Delaware, and under its Amended and Restated Certificate of
Incorporation and By-Laws, to issue the Common Stock reserved for issuance under
the Plans, and that such shares of Common Stock are validly authorized shares of
Common Stock and when issued and delivered against payment therefor in
accordance with the terms of the Plans, will be validly issued, fully paid and
nonassessable.

      I hereby consent to the filing of this opinion with the Commission as
Exhibit 5.1 to the Registration Statement. I also consent to the reference to me
in Item 5, Interests of Named Experts and Counsel, of the Registration
Statement. In giving such consent, I do not thereby admit that I am in the
category of persons whose consent is required under Section 7 of the Securities
Act or the Rules and Regulations promulgated thereunder.

                                        Very truly yours,


                                        /s/ Peter J. Millones
                                        ----------------------------------------
                                        Peter J. Millones


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