The Amgun is a river in Khabarovsk Krai, Russia that flows northeast and joins the river Amur from the left, 146 km upstream from its outflow into sea. The length of the river is 723 km. The area of its basin is 55500 km2. The Amgun is formed by the confluence of the Ayakit and Suluk. Its main tributary is the Nimelen. The Amgun teems with fish, such as Siberian salmon, humpback salmon, sturgeon, and carp. The Baikal Amur Mainline railway enters the Amgun valley from the Dusse-Alin Tunnel and follows the river 180 km northeast to Beryozovy where it turns southeast to Komsomolsk-on-Amur. The Amgun was known as Xinggun River (興衮河) in Chinese. At its mouth is the village of Tyr which was a Chinese fort during the Ming and Qing dynasties.