The Dadu River, known in Tibetan as the Gyelmo Ngul Chu, is a major river located primarily in Sichuan province, southwestern China. The Dadu flows from the eastern Tibetan Plateau into the Sichuan Basin where it joins with the Min River, a tributary of the Yangtze River. Measured from its geographic source, the Dadu is actually longer than the Min and thus forms the main stem of the Min River system.

Sichuan is a province in Southwestern China occupying the Sichuan Basin and Tibetan Plateau between the Jinsha River on the west, the Daba Mountains in the north and the Yungui Plateau to the south. Sichuan's capital city is Chengdu; its population stands at 83 million. Sichuan neighbors Qinghai to the northwest, Gansu to the north, Shaanxi to the northeast, Chongqing to the east, Guizhou to the southeast, Yunnan to the south, and Tibet to the west.