THE INFORMATION IN THIS PROSPECTUS IS NOT COMPLETE AND MAY BE CHANGED. WE MAY NOT SELL THESE SECURITIES UNTIL THE REGISTRATION STATEMENT FILED WITH THE SECURITIES AND EXCHANGE COMMISSION IS EFFECTIVE. THIS PROSPECTUS IS NOT AN OFFER TO SELL THESE SECURITIES AND IS NOT SOLICITING AN OFFER TO BUY THESE SECURITIES IN ANY STATE WHERE THE OFFER OR SALE IS NOT PERMITTED.

SUBJECT TO COMPLETION, DATED MAY 11, 2004

PROSPECTUS

ORCHID BIOSCIENCES, INC.

$30,000,000

COMMON STOCK

We will offer shares of our common stock from time to time in amounts, at prices and on terms to be determined at or prior to the time of the offering. The aggregate offering price of the common stock that we may issue under this prospectus will not exceed $30,000,000. We will provide you with specific terms of the applicable offered common stock in one or more supplements to this prospectus.

This prospectus may not be used to sell common stock unless accompanied by a prospectus supplement describing the method and terms of the offering of the offered common stock. WE URGE YOU TO READ CAREFULLY THIS PROSPECTUS AND THE ACCOMPANYING PROSPECTUS SUPPLEMENT, WHICH WILL DESCRIBE THE SPECIFIC TERMS OF THE COMMON STOCK OFFERED, BEFORE YOU MAKE YOUR INVESTMENT DECISION.

Our common stock is quoted on the Nasdaq National Market under the symbol “ORCH.” On May 10, 2004, the last reported sale price of our common stock on the Nasdaq National Market was $7.18 per share. Prospective purchasers of our common stock are urged to obtain current information as to the market prices of our common stock.

INVESTING IN OUR COMMON STOCK INVOLVES RISKS, SEE “RISK FACTORS” BEGINNING ON PAGE 5.

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR PASSED UPON THE ADEQUACY OR ACCURACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

The date of this prospectus is                                  , 2004

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