The Ili River (Kazakh: Іле, İle; Russian: Или; Chinese: 伊犁河; pinyin: Yīlí Hé; Mongolian: Ил, literally "Bareness") is a river in northwestern China (Ili Kazakh Autonomous Prefecture of the Xinjiang Uighur Autonomous Region) and southeastern Kazakhstan (the Almaty Province).

It is 1,439 km (894 mi) long, 815 km (506 mi) of which is in Kazakhstan. It takes its beginning in eastern Tian Shan from the Tekes and Kunges (or Künes) rivers. The Ili River drains the basin between the Tian Shan and the Borohoro (P'o-lo-k'o-nu) Mountains to the north.

Flowing into Lake Balkhash it forms a large delta with vast wetland regions of lakes, marshes and thicket vegetation.

Earlier mentions of Ili river is in Mahmud al-Kashgari's dictionary of Turkic languages, the Dīwānu l-Luġat al-Turk, written in 1072-1074. In the book, author defines: Ili, name of a river. Turkic tribes of Yaghma, Tokhsi and Chiglig live on its banks. Turkish countries regard the river as their Jayhoun (Amu Darya) . The name is possibly originated from Uyghur word Il, means hook in English, resembling the river's geographical shape.