Born in 1961 in Wolfsberg, Austria, Martin Kušej studied German studies and Sports Science, and subsequently Theatre Direction at the University of Music and Performing Arts in Graz. He started out as an assistant director at the Salzburger Landestheater and the National Slovenian Theatre in Ljubljana. In 1987 he made his debut as a director with his staging of Es by Karl Schönherr. In 1990 he teamed up with Martin Zehetgruber and Sylvia Brandl to form the company my friend martin, premiering his piece Tode in three transport containers. In 1992, he staged his first play for the Residenztheater, Thomas Strittmatter's Irrlichter-Schrittmacher.
From 1993 Kušej was for a number of years engaged as a director at the Schauspiel Stuttgart. His staging of Sarah Kane's Cleansed was invited to the Festival Theaterformen in Hannover, as was his first opera, King Arthur by Purcell in 1996. Kušej went on to direct at the Thalia Theater in Hamburg and the Burgtheater in Vienna, amongst others, and opera at the Opernhaus Zürich, the Staatsoper in Berlin and with De Nederlandse Opera, staging a legendary production of Shostakovich's Lady Macbeth of the Mtsensk District in 2006.