He studied composition and percussion instruments in Bern, Amsterdam and Berlin (under Dieter Schnebel). His music,filled with raw energy, is also sometimes referred to as speculative.
He has performed with many orchestras and ensembles, including Peter i Caspar Brötzmann (Massaker), Stephan Wittwer, Werner Lüdi, Marino Pliakas, Alex Buess, William Parker, Bill Laswell, Toshinori Kondo, Mark Trayle, Olaf Rupp, Holger Czukay and John Cale. Since 2005 Michael Wertmüller has been teaching at the Humboldt University in Berlin.
His best-known works include: Dunkel-Zeiten (1992), Das Zimmer (1993), William (1994) and Entleibung (2001).