William Rosenwald (August 19, 1903 – October 31, 1996) was an American businessman and philanthropist. His American Securities Corporation invested in other business including AMETEK and Western Union International. He helped establish the nationwide United Jewish Appeal in 1939 and made other charitable grants through the William Rosenwald Family Fund. His father was Julius Rosenwald, the former chairman of Sears, Roebuck and Company and a leading philanthropist whose Rosenwald Fund built 5,000 schools for black children in the South a few decades after the Civil War.