The 2003 International Formula 3000 season was the thirty-seventh season of the second-tier of Formula One feeder championship and also nineteenth season under the International Formula 3000 Championship moniker. It featured the 2003 FIA Formula 3000 International Championship with titles awarded for both Drivers and Teams. The championship was contested over ten events from 19 April to 13 September 2003.

The Formula 3000 International Championship was a motor racing series created by the Fédération Internationale de l'Automobile (FIA) in 1985 to become the final preparatory step for drivers hoping to enter Formula One. Formula Two had become too expensive, and was dominated by works-run cars with factory engines; the hope was that Formula 3000 would offer quicker, cheaper, more open racing. The series began as an open specification, then tyres were standardized from 1986 onwards, followed by engines and chassis in 1996. The series ran annually until 2004, and was replaced in 2005 by the GP2 Series.