The 1988 United States Senate election in California took place on November 8, 1988. Incumbent Senator Pete Wilson won re-election to a second term.
As of , this is the last time a Republican won a U.S. Senate election in California. This was also the first time since 1952 that an incumbent Senator was re-elected to this seat, and the last time until 2022 that a man would win a Senate election in California.
Counties that flipped from Republican to Democratic
Counties that flipped from Democratic to Republican