The 72nd Indianapolis 500 was held at the Indianapolis Motor Speedway in Speedway, Indiana, on Sunday May 29, 1988. Team Penske dominated the month, sweeping the top three starting positions with Rick Mears winning the pole position, Danny Sullivan at the center of the front row, and Al Unser, Sr. on the outside. Mears set a new track record, becoming the first driver to break the 220 mph barrier in time trials. On race day, the Penske teammates proceeded to lead 192 of the 200 laps, with Rick Mears taking the checkered flag, his third-career Indy 500 victory. The race represented the milestone 50th victory in Championship car racing for owner Roger Penske and Penske Racing.

The victory was the first of six consecutive Indy 500 wins by the Chevy Indy V-8 engine, and seven overall by Ilmor-constructed powerplants. The victory also marked a triumphant return of success for the Penske chassis (in this case the PC-17), after dismal results in 1987 (PC-16), and sparse use in the previous four seasons.

The race was the third event of the 1988 CART PPG Indy Car World Series, and was sanctioned by USAC.

Defending champion Al Unser, Sr. returned to Penske to join a three-car effort with Rick Mears and Danny Sullivan. After a dismal go around with the PC-16 ('87), Penske introduced the brand-new PC-17 ('88), with promise. Mears and Sullivan, respectively won the pole positions for the first two races of the CART season. For the third year, Penske was fielding the Chevy Ilmor Indy V-8 engine.

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