The Pearl River, also known by its Chinese name Zhujiang in Mandarin pinyin or Chu Kiang and formerly often known as the Canton River, is an extensive river system in southern China. The name "Pearl River" is also often used as a catch-all for the watersheds of the Xi, Bei, and Dong rivers of Guangdong. These rivers are all considered tributaries of the Pearl River because they share a common delta, the Pearl River Delta. Measured from the farthest reaches of the Xi River, the 2,400-kilometer-long Pearl River system is China's third-longest river, after the Yangtze River and the Yellow River, and second largest by volume, after the Yangtze. The 453,700 km² Pearl River Basin drains the majority of Liangguang, as well as parts of Yunnan, Guizhou, Hunan and Jiangxi in China; it also drains northern parts of Vietnam's Northeast Cao Bằng and Lạng Sơn provinces.
As well as referring to the system as a whole, the Pearl River name is also applied to a specific branch within the system. This Pearl River is the widest distributary within the delta, although notably short. The waters that converge east of the Bei Jiang are first referred to as the Pearl River just north of Guangzhou.