EXHIBIT 23.2


               CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS


We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Form S-3) and related Prospectus of OSI Pharmaceuticals,
Inc. for the registration of $200,000,000 4% Convertible Senior Subordinated
Notes due 2009 and 4,000,000 shares of its common stock and to the incorporation
by reference therein of our report dated February 1, 2002, with respect to the
financial statements of the Oncology Related Assets, Liabilities and Activities
of Gilead Sciences, Inc. included in the Current Report on Form 8-K/A of OSI
Pharmaceuticals, Inc. filed with the Securities and Exchange Commission on
March 6, 2002.

                                              /s/ ERNST & YOUNG LLP


Palo Alto, California
April 17, 2002