The 2004 1000 km of Monza was the first round of the 2004 Le Mans Series season, held at the Autodromo Nazionale Monza, Italy. It was run on May 9, 2004. Although proceeded by the 2003 1000km of Le Mans exhibition event, the 1000 km of Monza was the first official race of the new Le Mans Endurance Series.