With a length of 1,571 km (976 mi), the Yalong River flows from north to south through the Hengduan Mountains in western Sichuan Province.

The Yalong has its source in the Bayan Har Mountains on the Tibet–Qinghai Plateau in Chindu County, Yushu, Qinghai, where it is known as the Za Qu (Chinese: 扎曲).

[5] Here, water from the Yalong River has been diverted under the mountains as part of the Jinping-II Dam hydroelectric project.

The Yalong meets the main stem of the Yangtze (Jinsha) River in Panzhihua, Sichuan.

[6] The upper reaches of the Yalong have traditionally been inhabited by the Tibetan nomads of the historic region of Kham.