Garfield Morgan was born in Birmingham, England, in 1931. After a brief sojourn working as a trainee dental technician, he trained as an actor at a local drama school. His career began at the Arena Theatre in Birmingham in the fifties and he later became involved in both production and directing duties at The Marlow Theatre in Canterbury, Kent, and at The Library Theatre, Manchester. During the seventies he was Associate Director of Northgate Theatre and Associate Director of The Nottingham Playhouse.

His television career began in the mid-fifties and although initially playing small parts, during the sixties he began to take on bigger roles, including the part of Detective Chief Inspector Lewis in the BBC's long-running Softly Softly (1966) series. He often played policemen but none more famous than DCI Frank Haskins in The Sweeney (1975), opposite John Thaw and Dennis Waterman, during the seventies, where he was an admirable foil to Thaw's brash, renegade Inspector Jack Regan. He was also a regular in other TV series such as The Nineteenth Hole (1989), You Must Be the Husband (1987) and Shelley (1979), all during the eighties, and No Job for a Lady (1990) opposite Penelope Keith in the nineties.

He preferred acting on stage and in television so his film career was rather limited but he did have a decent role in The Odessa File (1974) in 1974.

In his personal life, early on he was married to the actress Dilys Laye before it ended in divorce. After a short illness, Morgan died from cancer on December 5, 2009. His former wife died just a few months previously.