UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the
Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):
July 23, 2003 (July 23, 2003)

AFFYMETRIX, INC.

(Exact name of registrant as specified in its charter)

DELAWARE	0-28218	77-0319159
(State of incorporation)	(Commission File Number)	(IRS Employer Identification No.)

3380 Central Expressway, Santa Clara, California 95051

(Address of principal executive offices) (Zip Code)

(408) 731-5000

(Registrant’s telephone number, including area code)

N/A

(Former name or former address, if changed since last report)

Item 7.  FINANCIAL STATEMENTS AND EXHIBITS

(c)Exhibits

Exhibit Number	Description
99.1	Press Release issued by Affymetrix, Inc. dated July 23, 2003.

Item 9.  REGULATION FD DISCLOSURE (Information Furnished in this Item 9 is Furnished Under Item 12. RESULTS OF OPERATIONS AND FINANCIAL CONDITION)

On July 23, 2003, Affymetrix, Inc. (the “Company”) issued a press release announcing the Company’s operating results for the quarter ended June 30, 2003.  A copy of the Company’s press release is attached hereto as Exhibit 99.1.

The information furnished in Items 9 and 12 of this Current Report on Form 8-K, including the exhibit, shall not be deemed to be incorporated by reference into Affymetrix’ filings with the SEC under the Securities Act of 1933.

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	AFFYMETRIX, INC.
	By:	/s/ Barbara A. Caulfield
		Name: Barbara A. Caulfield
		Title: Executive Vice President and General Counsel
Date:  July 23, 2003

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EXHIBIT INDEX

Exhibit Number	Description
99.1	Press Release issued by Affymetrix, Inc. dated July 23, 2003.

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