Grenville Kleiser (1868–1953) was a North American author. He was the author of a long list of inspirational books and guides to oratorical success and personal development. Kleiser also worked as an instructor in Public Speaking at Yale Divinity School, Yale University.

Kleiser was born in 1868 in Toronto, Ontario, Canada. He married Elizabeth Thompson in 1894. Grenville died on August 27, 1953 in New York City.