The 2003 GFS Marketplace 400 was the 23rd stock car race of the 2003 NASCAR Winston Cup Series. It was held on August 17, 2003 at Michigan International Speedway near Brooklyn, Michigan before a crowd of 150,000. The 200-lap race was won by Ryan Newman of the Penske Racing South team after he started from second position. Kevin Harvick of Richard Childress Racing finished second and Joe Gibbs Racing's Tony Stewart came in third.