The Anabar (Russian: Анабар, romanized: Anabar, in its upper course: Большая Куонамка Bolshaya Kuonamka; Yakut: Анаабыр, romanized: Anaabır) is a river in Sakha, Russia.

Its mean annual discharge is 564 cubic metres per second (19,900 cu ft/s), concentrated heavily in early summer when the ice that covers the river for most of the year thaws.

[2] The Uele river flows into the Laptev Sea close to the mouth of the Anabar, but it is not its tributary.

[5][6] In present times the basin of the Anabar river is notable as the location of the largest concentration of diamond deposits in the world outside of Africa and Australia.

These deposits made the Soviet Union into one of the world's largest producers of diamonds, and remain the economic mainstay of the area.