William Horn (birthdate unknown) was an American baseball pitcher in the pre-Negro leagues.

He played several years for Chicago teams like the Chicago Unions and Leland Giants.

[1] He also spent a couple of seasons with Iowa's Algona Brownies.

[3] Horn played with several popular players of the day, including Bill Gatewood, Bruce Petway, Dangerfield Talbert, Henry W. Moore, Chappie Johnson, Albert Toney, George Hopkins, and Harry Hyde.

[1]