The 2015 GoPro Grand Prix of Sonoma was an IndyCar motor race held on August 30, 2015, at the Sonoma Raceway in Sonoma, California. It was the 16th and final round of the 2015 IndyCar season and the 11th annual edition of the event. Contested over 85 laps, the race was won by Chip Ganassi Racing driver Scott Dixon. Ryan Hunter-Reay of Andretti Autosport finished second and Charlie Kimball, Dixon's teammate, finished third.
Will Power, who was fastest in two of the three pre-race practice sessions and won the pole position, was the dominant factor of the early portion of the race, leading 26 of the first 34 laps. However, Power was taken out of contention after he was hit by his Team Penske teammate, Juan Pablo Montoya, shortly before the halfway point of the race. Chip Ganassi Racing teammates Sebastián Saavedra and Tony Kanaan stayed out for multiple laps and traded the lead, but after they both pitted, Dixon maintained as much fuel as he could and scored the win. There were two caution flags for fourteen laps, and ten lead changes amongst seven drivers.
With his win, Dixon earned his fourth IndyCar Drivers' Championship on account of a tiebreaker with Montoya, who finished sixth. Following a late-race spin, Graham Rahal fell from second to fourth in points. Power recovered to finish seventh in the race, and overtook third in championship standings. Hélio Castroneves, who set the fastest lap of the race, maintained fifth. Chevrolet had also won the Manufacturers' Championship over Honda.