David John Constant (born 9 November 1941) is a former English professional cricketer and cricket umpire. He played first-class cricket from 1961 to 1968 for Kent County Cricket Club and Leicestershire County Cricket Club. He later became an international umpire, officiating in 36 Test matches from 1971 to 1988 and 33 one-day internationals from 1972 to 2001.