Auto Club 400
Auto Club 400
Venue Auto Club Speedway
Sponsor Automobile Club of Southern California
First race 1997
Distance 400 miles (643.737 km)
Laps 200
California 500 Presented by NAPA (1997-1999)
NAPA Auto Parts 500 (2000-2002)
Auto Club 500 (2003-2010)

The Auto Club 400 is a Monster Energy Cup Series race held annually at the Auto Club Speedway in the spring. It has been run since 1997 and is held in conjunction with an Xfinity Series race the preceding day. The race has been sponsored by the Automobile Club of Southern California, which also owns naming rights to the track, since 2003. For the 2011 season, the race was reduced from 500 miles to 400 miles. It is the fifth race on the calendar.