The 2005 Sony HD 500 was a NASCAR Nextel Cup Series stock car race held on September 4, 2005 at California Speedway in Fontana, California. Contested over 254 laps on the 2-mile (3.2-kilometre) asphalt D-shaped oval, it was the twenty-fifth race of the 2005 NASCAR Nextel Cup Series season. The race was extended from 250 laps because of a green–white–checkered finish.