Mentor Graphics, Inc is a US-based multinational corporation dealing in electronic design automation (EDA) for electrical engineering and electronics, as of 2004, ranked third in the EDA industry it helped create. The company, founded in 1981, is headquartered in Wilsonville, Oregon, and employs 4,000 people worldwide.

In 1981, the idea of computer-aided design for electronics as the foundation of a company occurred to several groups - those who founded Mentor, Valid Logic Systems, and Daisy Systems. One of the main distinctions between these groups was that the founding engineers of Mentor, whose backgrounds were in software development at Tektronix, ruled out designing and manufacturing proprietary computers to run their software applications. They felt that hardware was going to become a commodity owned by big computer companies, so instead they would select an existing computer system as the hardware platform for the Computer Aided Engineering (CAE) programs they would build.

By February 1981, most of the start-up team had been identified; by March, the three executive founders, Tom Bruggere, Gerry Langeler and Dave Moffenbeier had left Tektronix, and by May the business plan was complete. The first round of money, $1 million, came from Sutter Hill, Greylock, and Venrock Associates. The next round was $2 million from five venture capital firms, and in April 1983 a third round raised $7 million more. Mentor Graphics was one of the first companies to attract venture capital to Oregon.