William Hendrick Foster (June 12, 1904 – September 16, 1978) was an American left-handed pitcher in baseball's Negro leagues in the 1920s and 1930s, and had a career record of 143-69.
He was elected to the Baseball Hall of Fame in 1996.
Foster was the much-younger half-brother of Rube Foster, a Negro league player, pioneer, and fellow Hall of Famer.