Gregory James Philip Farrell (born 19 March 1944) is a Scottish former professional footballer.
Beginning his career at Birmingham City, Farrell found his chances limited and George Swindin signed him for a moderate fee to play for Cardiff City in March 1964. Playing as a winger, he often showed flashes of brilliance, including scoring one and supplying four other goals during a 5–3 win over Middlesbrough in May 1966. He eventually left the club in 1967 to sign for Bury. Farrell later went on to play in South Africa before retiring.