The 1978 Transamerica Open, also known as the Pacific Coast Championships, was a men's tennis tournament played on indoor carpet courts at the Cow Palace in San Francisco, California in the United States. The event was part of the 1978 Grand Prix circuit and Barry MacKay was the tournament director. It was the 90th edition of the tournament and ran from September 25 through October 2, 1978. The singles event had a field of 64 players. Eighth-seeded John McEnroe won the singles title and $24,000 first prize money.[3]