Munro Leaf (December 4, 1905 – December 21, 1976), was an American author of children's literature. He's best known for his 1936 book The Story of Ferdinand, a story about a bull who preferred smelling flowers to bullfighting. The book sparked considerable controversy, as it was seen by some as pacifist; it was consequently banned in Nazi Germany.

Born in Hamilton, Maryland, he graduated from the University of Maryland in 1927, and from Harvard University with a master's degree in English literature in 1931. During the Second World War, he and Ted Geisel (a.k.a. Dr. Seuss) created the pamphlet, This Is Ann, about a mosquito who spread malaria to men who failed to take precautions.