The 1968 United States Senate election in Alaska took place on November 5, 1968. Incumbent Democratic U.S. Senator Ernest Gruening ran for a second full term in office but finished behind Speaker of the Alaska House of Representatives Mike Gravel in the Democratic primary. Gruening launched an write-in bid for the seat in the general election, but finished third to Gravel and Republican former Anchorage mayor Elmer Rasmuson.
This would be the first of 3 times where the incumbent holder of Alaska's Class 3 U.S. Senate seat was defeated in the primary while running for re-election.
Future Senator Ted Stevens also ran in the Republican primary, but lost to Rasmuson by around 1,000 votes. When incumbent Democratic Class 2 Senator Bob Bartlett died that December, Governor Wally Hickel appointed Stevens to the vacant seat, giving Stevens a seniority advantage of 10 days over the incoming Gravel.