Donets River, a river in eastern Europe. It is the main tributary of the Don River. The Donets begins in the Central Russian Uplands and flows southeasterly, principally through Ukraine, for about 680 miles (1,094 km). The Donets is navigable mainly in its lower course. Its chief tributary is the Oskol River.

The Donets Basin, or Donbas, is a region between the Sea of Azov and the middle course of the Donets River. The cities of Donetsk, Makeyevka, Gorlovka, Luhansk, and Kramatorsk are in this highly populated region, which is a primary center of heavy industry in Ukraine. Huge deposits of coal account for the industrial growth of the Donbas. Iron ores are readily available from nearby Krivoy Rog and Kerch. Major products include coal, iron and steel, heavy machinery, chemicals, and machine tools.