Tehran (1941–1966) was a British Thoroughbred racehorse and sire, who raced during World War II and was best known for winning the classic St Leger in 1944. After showing little ability as a two-year-old he improved in the following spring to win the Culford Stakes on his three-year-old debut. He ran third in the 2000 Guineas and was narrowly beaten into second place in the Derby Stakes. After winning the Whepstead Stakes he recorded his biggest win when defeating a strong field in a substitute St Leger. He won his first three races in 1945 and finished second in the Ascot Gold Cup. He later became a successful breeding stallion, siring several major winners including Tulyar.