Klaus Lang (born 26 April 1971 in Graz) is an Austrian composer, concert organist, improviser, and academic teacher. His opera Die Architektur des Regens (The Architecture of Rain) after the Noh play Shiga by Zeami was premiered at the Munich Biennale in 2008. In 2006, Lang was appointed Professor of composition at the University of Music and Performing Arts, Graz. In 2010 he was awarded the Andrzej-Dobrowolski-Preis of the Steiermark.