Bicycle motocross or BMX is a sport involving bicycles that race in a motocross style on tracks with a starting gate and obstacles.

BMX emerged in the early 1970s in southern California, when children inspired by the motocross stars of the era began racing their bicycles on dirt trails. In the mid-1970s, BMX racing was an unusual phenomenon. Teenagers and children in California raced on standard road bicycles around special tracks on uneven roads. Imitating motocross races, they competed against each other on uneven roads wearing motocross gear. In 1972, the documentary film “On Any Sunday” dedicated to motorcycle racing was associated with inspiring a national movement across the United States. Its opening scene depicted children riding Sting-Ray bicycles on uneven trails. By the middle of that decade, the sport had reached a very large audience, and manufacturers began producing bicycles specially designed for this sport. BMX was included in the International Olympic Committee's program in 2003 and was held for the first time at the 2008 Beijing Summer Olympic Games. During these Olympic Games, BMX was organized for both men and women. The first Olympic champions in BMX were Māris Štrombergs from Latvia among men and Anne-Caroline Chausson from France among women. On 28 May 2011, 24-year-old BMX athlete Jed Mildon set a world record by performing a triple backflip on a BMX bicycle.