William Jacob Demko (December 20, 1895 – August 8, 1957) was a U.S. soccer defender^[1] who was a member of the U.S. soccer team at the 1924 Summer Olympics. Demko earned two cap with the U.S. national team in 1924. While Demko was a member of the U.S. team at the Olympics, he did not play in the two U.S. games.^[2] However, following the tournament, the U.S. had two exhibition games. Demko played in both, a win over Poland and a loss to Ireland.^[3]

He was born in Philadelphia, Pennsylvania.