EXHIBIT (a)(1)(F)

                         NOTICE OF WITHDRAWAL OF TENDER

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If you previously accepted Affymetrix' offer to exchange your options, but you
would like to change your decision and withdraw your tender, you must sign this
Notice of Withdrawal and return it to us no later than 5:00 p.m., Pacific Time,
on Friday, April 5, 2002, unless the offer is extended. If you have questions,
please contact the Human Resources Department representative for the exchange
offer. You can find a list of representatives, together with their contact
information, at the back of the Offer to Exchange referred to below.
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To Affymetrix, Inc.:

         I previously received a copy of the Offer to Exchange (dated March 7,
2002) and a Letter of Transmittal. I signed and returned the Letter of
Transmittal, in which I chose to accept Affymetrix' offer to exchange my
options. I now wish to withdraw my tender. I understand that by signing this
Notice of Withdrawal and delivering it to you, I will be withdrawing my
previous acceptance of the offer. I have read and understand all of the terms
and conditions of the offer to exchange options, including the consequences of
a withdrawal.

         I understand that in order to withdraw, I must sign, date and deliver
this Notice of Withdrawal to you so that you receive it before 5:00 p.m.,
Pacific Time, on Friday, April 5, 2002, or, if Affymetrix, Inc. extends the
deadline to exchange options, before the extended expiration of the offer.

         By rejecting the offer to exchange options, I understand that I will
not receive any new options and I will keep my old options (with the same
exercise price as before). These options will continue to be governed by the
stock option plan(s) under which they were granted and existing option grant
documents between Affymetrix, Inc. and me.

         I have completed and signed the following exactly as my name appears
on my original Letter of Transmittal.

         I do not accept the offer to exchange options.



Signature: __________________________________

Date:  _____________, 2002

Name: _______________________________________
         (Please Print)

Tax ID/Social Security No.: _________________