William Cornelius may refer to:
William Cornelius (cricketer) (1915–2005), Australian cricketer Willie Cornelius (1906–1989), American baseball pitcher in the Negro leagues Billy Cornelius (1898–?), English professional football player and manager
See also William Cornelius Reichel (1824–1876), Moravian author in the United States William Cornelius Van Horne (1843–1915), American businessman, industrialist, and railroad magnate