Robert James Percival Marshall, OAM (10 April 1910 – 23 February 2004) was a noted Australian amateur player of English billiards. He won the World Amateur Billiards Championship in 1936, 1938, 1951 and 1962 and was runner-up three times, as well as a national snooker champion. Marshall dominated amateur billiards before and after the war with a career that spanned six decades, broken by retirements in 1963 and 1970 followed by come-backs.