George Sleeman (August 1, 1841 – December 16, 1926) was a brewer, a major figure in Canadian baseball, and a politician in Ontario, Canada.

The family moved to Guelph in 1857 and in 1859, he became general manager of his father's Silver Creek Brewery; six years later he became a partner.

[4] The family lived in Guelph, later in a gothic custom-built mansion that was completed in 1891 at an estimated $30,000, near what is now called Silver Creek Parkway.

[9] Sleeman retired from the family business in 1905 and died in Guelph in 1926 at the age of 85 after undergoing an operation for an obstructed bowel.

[12] Sleeman had been a pitcher for the Guelph Maple Leafs baseball club and later became the team's financial backer.

In 1869, the Leafs squad won the Canadian championship and Sleeman was named president of the club.