The 1924 United States Senate election in South Dakota took place on November 4, 1924. Incumbent Senator Thomas Sterling ran for re-election to a third term, but he was defeated in the Republican primary by Governor William H. McMaster. In the general election, McMaster was opposed by attorney Ulysses Simpson Grant Cherry, the Democratic nominee, and several independent candidates. McMaster defeated his opponents by a wide margin, but fell far short of a majority, winning only 44% of the vote.