Asbjørn Schaathun was educated at the Norwegian Academy of Music and the Royal College of Music in London. Further studies led him to IRCAM, the Institute for musical/acoustical research and coordination in Paris. His stay at IRCAM culminated, in 1992, in the commission 'Double Portrait' for violin, ensemble and electronics.
Schaathun has been a pioneer in computer-aided composition in his native country of Norway. Besides his work as a composer, he has also written several articles on other composers and their music. Furthermore, he is the founder of the Norwegian Academy of Music's Contemporary Ensemble and its professional successor the Oslo Sinfonietta.
Asbjørn Schaathun has received several prizes for his work. Among others, he received the the Gaudeamus Foundation's Louis Vuitton Prize for the bass-clarinet concerto, 'Actions, Interpolations and Analyses' in 1991. In 1992 he was awarded the Norwegian assosiation of Critic's Prize and the same year he also received Bang & Olufsen's Music Prize. In 2008 he was awarded the Lindeman Prize, Norway's largest music prize, for "his tremendous work within Norwegian music."
Schaathun has also been heavily involved in music politics in Norway and Scandinavia. Apart from numerous smaller positions, he held the chair of the Norwegian Composer’s Society in the period 2006-12 as well as the chair of The Nordic Composer’s Council from 2010-12.
From 2013 he is professor in composition at the Norwegian State Academy of Music.