Diane Cilento, a daughter of Sir Ralph and Lady Phyllis Cilento, grew up on Queensland's Sunshine Coast. She moved to New York at the age of sixteen and later won a scholarship to the Royal Academy of Dramatic Art, London.
Cilento was a noted actress during the 1950s and 1960s, receiving nominations for both Tony and Oscar awards. Cilento had three marriages: to Italian Andrea Volpe (1956-1960), Scot Sean Connery (1962-1973) and British playwright Anthony Schaffer (from 1985 until Schaffer's death in 2001). With Shaffer, Cilento established the open-air theatre Karnak Playhouse in the Daintree, North Queensland.
Cilento is a sister of Ruth Yolanda Cilento and Margaret Cilento (qq.v.).
