A 1904 photograph of Gleason as the second baseman for the Philadelphia Phillies.

A 1919 photograph of Gleason as the manager of the Chicago White Sox.

William J. "Kid" Gleason (October 26, 1866 — January 2, 1933) was an American professional athlete and Major League baseball player and manager. Gleason is best known for his involvement as a betrayed manager in the 1919 Chicago White Sox, the team made infamous by the Black Sox scandal, Gleason's players conspired to intentionally lose the World Series.

The scandal resulted in lifetime bans from baseball for eight White Sox players. Gleason, however, had no knowledge of the conspiracy, and although he felt betrayed and disappointed by his 1919 team, he continued to manage the White Sox until 1923.

Gleason was born in Camden, New Jersey. He acquired the nickname "Kid" early in life, not only because of his short stature but also because of his his energetic, youthful nature. Gleason debuted as a pitcher with the Philadelphia Phillies on April 20, 1888. He enjoyed several successful seasons, especially 1891 (38 wins), before becoming a second baseman. Gleason achieved a .261 career batting average before retiring after the 1912 season. He began his career as a manager with the White Sox on December 31, 1918.

After leaving the White Sox in 1923, Kid Gleason would go on to coach under Manager Connie Mack with the Philadelphia Athletics until his death, of a heart ailment, in 1933, at the age of 68, in Philadelphia, Pennsylvania.