FOR IMMEDIATE RELEASE


Contact: Keithley Instruments, Inc.
28775 Aurora Road
Cleveland, Ohio 44139


KEITHLEY INSTRUMENTS PRESENTATION AT THE THOMAS WEISEL PARTNERS TEST AND MEASUREMENT CONFERENCE TO BE WEBCAST LIVE

Cleveland, Ohio - December 6, 2002 - Keithley Instruments, Inc. (NYSE:KEI), a leader in solutions for emerging measurement needs, today announced that Joseph P. Keithley, Chairman, President and Chief Executive Officer, will speak to the investment community at the Thomas Weisel Partners Test and Measurement Conference at TWP's New York Offices on December 11, 2002, at 9:40 a.m.

Interested investors can access the live webcast of the presentation through Keithley Instruments website at www.keithley.com under the Investor Relations section. A replay of the webcast will be available until January 11, 2003.


About Keithley Instruments. Keithley Instruments, Inc. provides optical and electrical measurement solutions from DC to RF to the wireless, semiconductor, optoelectronics, and other electronics manufacturing industries. Engineers and scientists around the world use Keithley's advanced hardware and software for process monitoring, production test, and basic research.

Products and company names listed are trademarks or trade names of their respective companies.


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