The 1970 NASCAR Grand National Series season began on Sunday January 18 and ended on Sunday November 22. Bobby Isaac was the champion of the series as NASCAR transitioned from the Grand National era to the Winston Cup era. Only one foreigner was racing that year, a Canadian named Frog Fagan (who finished 96th in the championship standings). It was also the last NASCAR national touring series season to feature a dirt track race until the 2013 NASCAR Camping World Truck Series, and the last time the Cup series raced on dirt until the 2021 NASCAR Cup Series.