John Stuart Lloyd Barnes (28 June 1920 – 1 June 2008) was a British film historian specialising in the early history of cinema. He co-founded the Barnes Museum of Cinematography with his brother William. The museum was one of the first museums devoted to film and became a focal point for scholars worldwide. Barnes is best known for a five-volume history of film titled The Beginnings of the Cinema in England, 1894-1901.