Torun Lian was born in Norway in 1956. She attended the Forsøksgymnaset in Oslo, followed by the agricultural school. In 1978 she began working as a prop master and stage designer at various theaters in Norway and taught dramatic writing at the Norwegian Film School and the State Institute for Film.
In the eighties, Fjernsynsteatret, a division of the Norwegian broadcaster NRK, produced three plays by Lian for television, »Colaengelen« (tr: Cola Angel), »Sand«, and »Natt/Hotell« (tr: Night/Hotel), which were also published in book form and won Lian the Tarjei Vesaas Debutant Prize. Later, Lian became famous with her television series for children. The collaboration with the director Berit Nesheim resulted in the young adult books »Frida« (1990) and »Frida – med hjertet i hånden« (1991; tr: Frida – Straight from the Heart), which were also filmed and awarded the Prix Jeunesse. Here, the main theme is the difficult time of early puberty. Eleven-year-old Frida also has to assert herself against her older sister, who apparently only has boys on her mind and is constantly applying make-up and getting new clothes. Lian describes with sensitivity and wit the confusing feelings of adolescents in a small family with a single mother. For »Bare skyer beveger stjernene« (1991; tr: Only Clouds Move the Stars) Lian was awarded the Nordic Children’s Literature Prize. She also wrote the screenplay for the film adaptation and made her début as a director. The film was awarded the Crystal Bear at the Berlinale 1999 and the grand prize at the 40th Nordic Film Days in Lübeck. The plot focuses on eleven-year-old Maria, who retreats into herself after her little brother dies. She can only overcome her grief after meeting her peer Jakob. In 2008 Lian published her first novel for adults »Undrene i vår familie« (tr: The Miracles of our Family). Starting in 2014, she began a series of books for children aged eight and over about »Alice Andersen«, a shy little girl who struggles with her fears and struggles to assert herself in school and among her friends. In 2015 she published »Reserveprinsesse Andersen« (tr: Alice Andersen: Backup Princess) which was awarded the Brage Prize. Four volumes have appeared to date, each illustrated by the German Youth Literature Prize winner Øyvind Torseter.
From 2004 to 2006, Lian was a consultant for feature films at the Norwegian Film Fund. She lives in Oslo, Norway.