Margaret Trist was born at Dalby and attended St Columba's Convent. She moved to Sydney in 1931 and became very active in the city's literary world. She met her husband, Frank Trist, at a meeting of the Junior Literary Society and they were married in December 1933. During the 1930s, Trist worked as a secretary for several organisations in Sydney and was a script assistant at the ABC for the poet and editor John Thompson.

Trist was also writing short stories and her work was published in a number of magazines and newspapers, including Southerly, the Bulletin, ABC Weekly, Australian New Writing, Young Australia, The Home and the Daily Mirror. She published her first collection of stories, In the Sun, at her own expense in 1943. But she reached a wider audience with her first novel, Now that We're Laughing (1945), which was published by Angus and Robertson in Sydney and Harper and Brothers in New York. This was followed in 1947 by a second collection of short stories, What Else Is There?, and a novel, Daddy. Trist is perhaps best known for Morning in Queensland (1958), a novel for young adults, which was first published in England and the USA. In 1991 the novel was published by University of Queensland Press with the new title, Tansy.

Margaret Trist joined the Sydney English Association in 1944 and was a member of the Executive Committee for many years. Widely anthologised, Trist's fiction has been praised for its humour, precise characterisation and insight into small town life. She died in Sydney in 1986.