1990 IndyCar season

The 1990 IndyCar season, the twelfth in the CART era of U.S. open-wheel racing, consisted of 17 races, beginning in Avondale, Arizona on April 8 and concluding in Monterey, California on October 21. There was one non-championship event, the Marlboro Challenge. The PPG Indy Car World Series Drivers' Champion was Al Unser, Jr. and the Indianapolis 500 winner was Arie Luyendyk. Rookie of the Year was Eddie Cheever. The 74th Indianapolis 500 was sanctioned by the USAC, but counted in the CART points standings.

Drivers and constructors
The following teams and drivers competed for the 1990 Indy Car World Series.

Races
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 * Indianapolis was USAC-sanctioned but counted towards the CART title.

Final driver standings
Point Scoring System:
 * Points are awarded based on each driver's resulting place (regardless of whether the car is running at the end of the race):

Bonus Points:
 * 1 For Pole Position
 * 1 For Leading The Most Laps Of The Race

Nation's Cup

 * Top result per race counts towards Nation's Cup.