Marcus Weiss studied saxophone at the Basel Academy of Music with Iwan Roth, as well as philosophy and saxophone (Frederick L. Hemke) at Northwestern University in Chicago. 1989: Soloist Prize of the Swiss Tonkünstler Association.
He performs as a soloist with many European orchestras and ensembles, and also as a chamber musician with the Trio Accanto and with the saxophone ensemble Xasax/Paris. He has collaborated with the following composers, among others, who wrote works for him: Mark Andre, Georges Aperghis, John Cage, Péter Eötvös, Beat Furrer, Vinko Globokar, Georg-Friedrich Haas, Toshio Hosokawa, Yu Kuwabara, Hanspeter Kyburz, Helmut Lachenmann, Misato Mochizuki, Giorgio Netti, Stefan Prins, Rebecca Saunders, Salvatore Sciarrino, Karlheinz Stockhausen, Nadir Vassena.
In 2010, the specialist book The Techniques of Saxophone Playing was published by Bärenreiter.
Since 1995 Marcus Weiss is professor for saxophone and chamber music at the Basel Academy of Music. He directs the study programme “Master in Specialized Performance, Contemporary Music", which he designs together with his colleagues Sarah Maria Sun, Yaron Deutsch and Mike Svoboda.
He regularly gives master classes at European (Paris, Madrid, London, Berlin, Vienna, Porto, Riga, etc.) and American universities. For many years he has been a lecturer at the "Darmstädter Ferienkurse für neue Musik" and at the Ensemble-Akademie IMPULS in Graz. He also curates festivals for new music (Rümlingen and Zurich).