The 2009 Indy Grand Prix of Sonoma was the fourteenth round of the 17-race 2009 IndyCar Series season, and was held on August 23, 2009 at the 2.303-mile (3.706 km) Infineon Raceway in Sonoma, California.

Will Power and Nelson Philippe both missed the race, after they were hospitalized after a practice accident on Saturday.

Philippe spun at the blind turn 3A, and stalled the car on-track.

E. J. Viso hit the Frenchman's car, before Power t-boned it a few seconds later.

Power suffered fractures to two lumbar vertebrae, Philippe fractured his left foot and Viso escaped uninjured.