Marc Duez (born 15 April 1957 in Verviers) is a race and rally driver from Belgium.
He won the 24 Hours Nürburgring several times, and also the 24 Hours Spa.
Duez also has competed in the 24 Hours of Le Mans and the Andros Trophy.
For years now Marc Duez has been a representative for the RACB, the Royal Automobil Club of Belgium. He strongly promotes the Driver's Academy and the Belgian Racing Circuits.
Also since 2009 Marc Duez has been racing for Fun Still Exists, also known as FSE. For this team he has been racing the Legend Boucles de Spa 2010 and Ypres Historic Rally 2010, and also the Legend Boucles de Spa 2011.