Mati Unt was an Estonian writer, essayist and theatre director.

Unt's first novel, written at the age of 18 after having finished high school, was Hüvasti, kollane kass (Goodbye, Yellow Cat). This made him famous all over Estonia. He studied literature and journalism at Tartu University in Tartu, Estonia.

After this precocious beginning‚ Unt arranged a wide call in the artistic and intellectual circles of Estonia as a writer of the fiction, plays, and criticism. His books The Moon Like the Outgoing Sun, The Debt (1964), On the Existence of life in space, and The Black Motorcyclist rocketed Unt to the top of the novelist world in Estonia. In addition, he served a purpose in bringing avantgarde theatre to post-Soviet Union Estonia. Unt was well known as a theatre director. In 1981, he became a director of the Youth Theatre in Tallinn.

In 1979, his novel Autumn Ball (adapted to a movie in 2007 by Veiko Õunpuu) brought him international recognition. Other books include 1990s Notebook of a Donor and the 2001 play Graal!. Films based on Unt's works Tühirand and Sügisball have been created after his death.

Mati Unt died in 2005. He is buried in the Metsakalmistu cemetery in Tallinn.