The Heilongjiang River (the Amur River) is the northernmost major stream of China. It forms most of the northeastern boundary with Russia. The source of the Heilongjiang River is formed in Mohe of China by the Shileka River in the east of Mount Kent in Mongolia, and the Argun River in the west of Mount Xiaoxinganling in China.     

The Heilongjiang River, running through China, Russia and Mongolia, is the 11^th largest river in the world, with 4,370 kilometers in length and a drainage area of 1.84 million square kilometers. 48% of the Heilongjiang River is in China.

The upper reaches of the river lie between the source and the mouth of the Jieya River, with a total length of 900 kilometers; the middle reaches stretch from the Jieya River down to the Wusuli River, with a total length of 1,000 kilometers; and the lower, from the Wusuli River to the Sea of Okhotsk in Russia, with a total length of 950 kilometers.

Among the over 200 anabranches of the Heilongjiang River, rivers of Songhuajiang, Wusuli, and Jieya are of larger size. The Songhuajiang River, with its source in the Heavenly Pond, is the largest branch, covering a drainage area of 550,000 square kilometers. The Wusuli River, with a total length of 905 kilometers, covers a drainage area of 187,000 square kilometers.   

The Heilongjiang River abounds in hydroelectric resources, with an annual potential of up to 32 million kilowatts. Besides, it is a major base of fishery resources in north China.