George Sleeman (August 1, 1841 – December 16, 1926) was a brewer, a major figure in Canadian baseball, and a politician in Ontario, Canada. He was mayor of Guelph from 1880 to 1882 and from 1905 to 1906. Sleeman was also the president of the Guelph Rifle Association for 20 years, president of the Guelph Turf Club, president of the Guelph Bicycle Club, and, for four years, president of the Ontario Brewing and Malting Association. He helped establish the Royal City Curling Club. His brewery also sponsored an amateur baseball team called the Silver Creek Club.