William Wilder Heusner, Jr. (June 28, 1927 – August 9, 2002) was an American competition swimmer and Pan American Games champion. Heusner represented the United States at the 1948 Summer Olympics in London, England. He competed in the preliminary heats of the men's 400-meter freestyle and finished eighth in the final of the men's 1,500-meter freestyle. At the 1951 Pan American Games, Heusner won the silver medal in the men's 400-meter freestyle. He was also a gold medal as a member of the winning U.S. team in the men's 4×200-meter freestyle relay event, alongside relay teammates Dick Cleveland, Burwell Jones, and Ronald Gora.