John Dexter (2 August 1925 – 23 March 1990) was an English theatre, opera and film director.

Born in Derby, Derbyshire, England, Dexter left school at the age of fourteen to serve in the British Army during the Second World War. Following the war, he began working as a stage actor before turning to producing and directing shows for repertory companies. In 1957, he was appointed Associate Director of the English Stage Company based at the Royal Court.

Dexter's first great success was his production of Roots, in 1959, which brought Joan Plowright to prominence. He went on to direct Toys in the Attic (with Wendy Hiller, 1960) and Saint Joan (1963). In 1964, he was named Associate Director of the National Theatre of Great Britain, and he produced The Royal Hunt of the Sun (1964).

That year, he also directed Othello, with Sir Laurence Olivier, Maggie Smith and Frank Finlay. It was considered a tremendous success. RCA recorded an audio version, and, the following year, Stuart Burge made a film of the production (now available on DVD) for BHE Films.

Dexter continued with Hamlet (with music by Conrad Susa, 1969), Equus (one of his triumphs, 1973), Trevor Griffiths's The Party (Lord Olivier's final stage appearance, 1973), Phaedra Britannica (with his friend, Diana Rigg, 1975), The Merchant (aka, Shylock, 1977), As You Like It (with music by Harrison Birtwistle, 1979), Life of Galileo (with Sir Michael Gambon, 1980), The Glass Menagerie (with Jessica Tandy, 1983) and Julius Caesar (1988). His final great success was M. Butterfly (1988), on Broadway, and the following year, he staged Die Dreigroschenoper there (with Sting as Macheath), which was to be his final production.

Dexter's debut feature-film was The Virgin Soldiers (with Lynn Redgrave, 1969). His second film was The Sidelong Glances of a Pigeon Kicker (aka, Pigeons, with Elaine Stritch, 1970); his third was I Want What I Want (1972).

For Granada Television, Dexter directed Twelfth Night, with Sir Alec Guinness and Sir Ralph Richardson in 1969.