The 2018 Monster Energy NASCAR Cup Series was the 70th season of NASCAR professional stock car racing in the United States, and the 47th modern-era Cup series season. The season began at Daytona International Speedway with the Advance Auto Parts Clash, the Can-Am Duel qualifying races and the 60th running of the Daytona 500. The regular season ended with the Brickyard 400 on September 9, 2018. The playoffs ended with the Ford EcoBoost 400 at Homestead-Miami Speedway on November 18, 2018. Martin Truex Jr. was the defending champion, having won his first in the series.

The Brickyard 400 is an annual NASCAR Cup Series points race held at the Indianapolis Motor Speedway in Speedway, Indiana. The inaugural race was held in 1994 and was the first race other than the Indianapolis 500 to be held at the Indianapolis Motor Speedway since 1916. In its inaugural running, the Brickyard 400 became NASCAR's most-attended event, drawing an estimated crowd of more than 250,000 spectators. The race also paid one of NASCAR's highest purses. From 1994 to 2020, the race was held on the 2.5-mile oval, for a distance of 400 miles. The race was put on hiatus for three years (2021–2023) in favor of the Verizon 200 at the Brickyard which was run on a combined road course and run a distance of 200-mile (321.869 km). However, the race will return to the oval for the 2024 season.