Marcel Fässler (born 27 May 1976) is a Swiss professional racing driver. He has competed in the FIA World Endurance Championship as part of Audi Sport Team Joest with co-drivers André Lotterer and Benoît Tréluyer since 2010, winning the 24 Hours of Le Mans three times (2011, 2012, and 2014) and capturing the World Endurance Drivers' Championship in 2012.
Born in Einsiedeln, Fässler began competing in the Deutsche Tourenwagen Masters for Mercedes-Benz when it resumed in 2000. He finished 4th with no wins in 2000, 4th with one win in 2001 and in 2002 and 3rd with one win in 2003, all four seasons with a Mercedes-Benz CLK. He moved to Opel and an Opel Vectra GTS V8 for 2004 and 2005, where he finished 9th and 12th with no wins after which the brand retired from the DTM.
Fässler switched to sports cars in 2006, finishing second at the Spa 24 Hours in a Phoenix Aston Martin DBR9 and collecting two overall podiums at the Le Mans Series for Swiss Spirit.