Sir John Layton Jarvis (27 December 1887 – 20 June 1968), known as Jack Jarvis was a British trainer of racehorses. Born into a racing family, Jarvis had a brief but successful career as a jockey before taking up training. He was one of the most prominent British trainers of the mid 20th century, winning nine British Classic Races and being the British flat racing Champion Trainer on three occasions. In 1967 he became the first trainer to be knighted for services to horse racing.