Keithley Instruments Announces Dividend

Keithley Instruments, Inc. (NYSE:KEI), a world leader in advanced electrical test instruments and systems, today announced its quarterly cash dividend in the amount of $0.0125 per Common Share. The quarterly dividend is $0.01 per Class B Common Share. The dividend is payable September 30, 2009, to shareholders of record at the close of business on September 16, 2009.

About Keithley Instruments, Inc.

With more than 60 years of measurement expertise, Keithley Instruments has become a world leader in advanced electrical test instruments and systems from DC to RF (radio frequency). Our customers are scientists and engineers in the worldwide electronics industry involved with advanced materials research, semiconductor device development and fabrication, and the production of end products such as portable wireless devices. The value we provide them is a combination of products for their critical measurement needs and a rich understanding of their applications to improve the quality of their products and reduce their cost of test.