The 1991 Peak Antifreeze 500 was the 23rd stock car race of the 1991 NASCAR Winston Cup Series season and the 21st iteration of the event.

At race's end, Leo Jackson Motorsports driver Harry Gant would manage to dominate a majority of the race, lapping the field to take his 15th career NASCAR Winston Cup Series victory, his fourth victory of the season, and his third straight victory.

In addition to NASCAR, the track also hosted USAC and the NTT IndyCar Series.

For this specific race, positions 21-40 would be decided on time,[4] and depending on who needed it, a select amount of positions were given to cars who had not otherwise qualified on time but were high enough in owner's points; up to two were given.

Alan Kulwicki, driving for his own AK Racing team, would win the pole, setting a time of 24.519 and an average speed of 146.825 miles per hour (236.292 km/h) in the first round.