William Henry Harrison III Republican Teno Roncalio Democratic The 1964 United States House of Representatives election in Wyoming was held on November 3, 1964, to elect the United States representative from Wyoming's at-large congressional district.

Incumbent Republican Representative William Henry Harrison III sought reelection to a fifth term, but was defeated by Democratic nominee Teno Roncalio.

[2][3] Walter Phelan, the chairman of the Wyoming Democratic Central Committee, listed International Joint Commission chairman Teno Roncalio, U.S. Marshall John Terril, Natrona County Attorney Harry Leimback, state Senator Ed Kendig, state Representative Edgar Herschler, Cheyenne Mayor Bill Nation, William Hill, and Ray Whitaker as possible candidates for the Democratic nomination for the United States House of Representatives.

[4] On April 28, 1964, Roncalio announced that he would seek the Democratic nomination for the United States House of Representatives.

[7] Hepburn Armstrong, who served as the Democratic nominee during the 1962 election, also filed to run.