Union Cycliste Internationale (UCI) (English: International Cycling Union) is the world governing body for sports cycling and oversees international competitive cycling events. The UCI is based in Aigle, Switzerland.

The UCI issues racing licenses to riders and enforces disciplinary rules, such as in matters of doping. The UCI also manages the classification of races and the points ranking system in various cycling disciplines including mountain biking, road and track cycling, for both men and women, amateur and professional. It also oversees the World Championships.

The UCI was founded on 14 April 1900 in Paris by the national cycling organisations of Belgium, the United States, France, Italy, and Switzerland. It replaced the International Cycling Association by setting up in opposition in a row over whether Great Britain should be allowed just one team at world championships or separate teams representing Scotland, Wales and Ireland. Britain found itself outflanked and it was not able to join the UCI - under the conditions the UCI had imposed - until 1903.