The 1981 CART PPG Indy Car World Series season, the third in the CART era of U.S. open-wheel racing, consisted of 11 races, beginning in Avondale, Arizona on March 22 and concluding at the same location on October 31.

The PPG Indy Car World Series Drivers' Champion was Rick Mears despite missing Round 2 at Milwaukee due to injuries sustained in the Indianapolis 500.

The Tony Bettenhausen 200 at Milwaukee was originally scheduled for August 2, but was rained out and postponed until September 5.

- The Detroit News Grand Prix was supposed to run for 150 miles, but was shortened due to a scoring error.

O  Oval/Speedway  R  Dedicated road course Note, the total time of the Norton Michigan 500 does not include red flag stoppage time as the race was stopped for nearly 1 hour due to a bad pit lane fire