Stock Car Racing is a form of automobile racing found mainly in the United States, Canada and Great Britain held largely on oval rings of between approximately a quarter-mile and 2.66 miles (about 0.4 to 4.2 kilometres) in length, but also raced occasionally on road courses.

A Stock Car, in the original sense of the term, is an automobile that has not been modified from its original factory configuration. Later the term stock car came to mean any production-based automobile used in racing.

The most prominent championship in stock car racing is the NASCAR championship, currently named the Sprint Cup after its sponsor Sprint Nextel, and previously known as Strictly Stock (1949), Grand National (1950-1970), Winston Cup (1971-2003), and Nextel Cup (2004-2007). It is the most popular racing series in the United States, drawing over 6 million spectators in 1997, an average live audience of over 190,000 people for each race.