The Tartar (Azerbaijani: Tərtərçay, Armenian: Թարթառ) is one of the tributaries of the Kura river located in Azerbaijan.

The river originates in the area where Qonqur, Alaköz and Mıxtökən mountain ranges meet on the Karabakh Plateau in the vicinity of the hot springs village of Istisu located in Kalbajar Rayon of Azerbaijan.

Sarsang reservoir was built on Tartar river in 1976 for electricity generation and irrigation purposes.

During spring and summer months, the snow melting in the mountains causes floods, making up 65–70% of the annual water flow.

'Hot Water' in Azerbaijani), which was occupied and ruined following the First Nagorno-Karabakh War, is located on the lower part of the river.