The 1970 United States Senate election in Hawaii took place on November 3, 1970. Incumbent Republican Senator Hiram Fong was re-elected to a third term in office, narrowly defeating Democratic businessman Cecil Heftel.
According to the Honolulu Star-Bulletin, Fong's support for the Vietnam War led to his close-call in the 1970 election. As of , this remains the last U.S. Senate election in Hawaii won by a Republican.