John Williams (born 8 June 1937) is a retired Welsh snooker referee. He presided over eleven World Championship finals, including the 1985 final between Dennis Taylor and Steve Davis.
Williams was born in Wrexham, Denbighshire, Wales. He was well-educated and passed his 11-Plus at the age of nine; and when he left school, he had obtained seven O-levels. He got a job in the local steel works, and passed up the opportunity of becoming a professional footballer, declining an invitation to join Bolton Wanderers as an amateur because he worked on Saturday mornings.
After nearly 20 years in the steel industry, he left to join the civil service as an executive officer in the Department of Employment. While at the civil service, he displayed his all-round sporting versatility by turning out regularly for the Wrexham civil service cricket team.
Williams started refereeing snooker matches during the mid 1960s, leaving the civil service in 1981 to become a full-time referee.
Williams was at the centre of many unusual incidents during his time as a professional refereeing career. He officiated in the 1973 World Snooker Championship quarter-final match between Fred Davis and Alex Higgins at the Manchester Exhibition Hall when rain stopped play. There was no TV coverage, but Granada TV cameras got an interest in this unusual event, bringing fame to Williams himself.