The 1956 United States House of Representatives election in Wyoming was held on November 6, 1956. Incumbent Republican Congressman Keith Thomson ran for re-election to a second term. He won the Republican primary unopposed and faced Democratic nominee Jerry A. O'Callaghan, a history instructor at the University of Wyoming and former journalist, in the general election. Thomson defeated O'Callaghan with 58 percent of the vote, slightly underperforming President Dwight D. Eisenhower's landslide victory in the state.