The 2003 FIA Sportscar Championship was the third season of FIA Sportscar Championship, an auto racing series regulated by the Fédération Internationale de l'Automobile and organized by the International Racing Series Ltd. It was the seventh and final season of the series dating back to the International Sports Racing Series of 1997. The series featured sports prototypes divided into two categories, SR1 and SR2, and awarded championships for drivers, constructors, and teams in both classes. The series began on 13 April 2003 and ended on 21 September 2003 after seven races in Europe.
Jan Lammers of the Netherlands won his second consecutive drivers championship for his Racing for HollandDome outfit, sharing the championship with countryman John Bosch. Mirko Savolid and Pierguiseppe Peroni also earned a repeat drivers championship in the SR2 category for Lucchini Engineering after winning in five of seven events.
Jan Lammers (pictured in 2011) won the FIA Sportscar Championship for Drivers for the second consecutive year
Points were awarded to the top eight finishers in each category. Entries were required to complete 60% of the race distance in order to be classified as a finisher and earn points. Drivers were required to complete 20% of the total race distance for their car to earn points. Teams scored points for only their highest finishing entry. For the 1000km Spa points were also awarded to the top eight in each category at half distance.