Dorian Leon Marlois Le Gallienne (19 April 1915 – 27 July 1963) was an Australian composer, teacher and music critic.
His father, an actor, was born in France, and his mother, a pianist who had studied with G. W. L. Marshall-Hall, was the daughter of the Assistant Astronomer at the Melbourne Observatory.
After leaving school, he studied with A. E. H. Nickson at the Melbourne Conservatorium and with Arthur Benjamin and Herbert Howells at the Royal College of Music in London in 1938.
In 1939, he travelled in Europe with Richard Downing, a future Chairman of the Australian Broadcasting Commission (ABC), and with whom he later lived in Melbourne in a mud-brick house at Eltham.
In 1967 the music critic Roger Covell wrote that Le Gallienne's Symphony was 'still the most accomplished and purposive ... written by an Australian'.