The 2015 NASCAR Sprint Cup Series was the 67th season of professional stock car racing in the United States and the 44th modern-era Cup season. The season began at Daytona International Speedway with the Sprint Unlimited exhibition race, the Budweiser Duels, and the Daytona 500. The season ended with the Ford EcoBoost 400 at Homestead-Miami Speedway. Kyle Busch won the championship, despite missing the first third of the season due to severe leg injuries suffered in an Xfinity Series race at Daytona. Busch also became the first Toyota driver to win a Cup championship. Despite not running the full season, Brett Moffitt was named Rookie of the Year.

Stock car racing is a form of automobile racing run on oval tracks and road courses measuring approximately 0.25 to 2.66 miles. It originally used production-model cars, hence the name "stock car", but is now run using cars specifically built for racing. It originated in the southern United States; its largest governing body is NASCAR. Its NASCAR Cup Series is the premier top-level series of professional stock car racing. Australia, Canada, New Zealand, Mexico, Brazil, Argentina, and the United Kingdom also have forms of stock car racing. Top-level races typically range between 200 and 600 miles in length.