Earl St. John (14 June 1892 – 26 February 1968) was an American film producer in overall charge of production for The Rank Organisation at Pinewood Studios from October 1950 to June 1964, and was credited as executive producer on 131 films. He was known as the "Earl of Pinewood". He was elected a Director of the Company in September, 1951.

John Davis of Rank called him "the greatest showman that The Rank Organisation has ever had, and probably the greatest showman to have lived in this country. "

His achievements including promoting Norman Wisdom and Peter Finch as film stars, and the box office success of Genevieve and Doctor in the House. However it has been argued "St John's fame has been completely overshadowed" by J. Arthur Rank and John Davis.

St. John was born in Baton Rouge, Louisiana. His father wanted him to become a soldier but he ran away from a military academy aged 17 and began his career as a page boy for Sarah Bernhardt's company.

St. John's uncle worked in the film business and he worked for him when he was 21. He worked as a poster boy then took two religious films around the US and Mexico. He worked during the Mexican Civil War and met Pancho Villa. He fell out with his uncle and joined the Mutual Film Company.

St. John served in France with the Texas division during World War I. He demobilised in Liverpool, England, and elected to stay on in the country.

In the early 1920s, St. John ran a small picture theatre in Manchester, the Ardwick Green Picture Theatre, and became successful. In 1924, he joined Paramount Theatres Limited, building up its circuit and opening the Plaza and Carlton cinemas. In 1930, they took over the Astoria Cinemas and St. John was responsible for them as well.

Paramount was bought out by Odeon in 1938 and St. John joined The Rank Organisation. In 1939 he became personal assistant to John Davis.