John Charles Sillett (born 20 July 1936) is an English football player and manager. He played for Chelsea, Coventry City and Plymouth Argyle. He won the Championship with Chelsea in 1955, playing alongside his brother Peter Sillett. He was manager of Coventry City from 1986 until 1990, winning the FA Cup in 1987, and also had two spells as manager of Hereford United.