Zhaltyr () is an endorheic lake in Akkuly District, Pavlodar Region, Kazakhstan.
Zhaltyr lake is near the southern end of Malybay village and about west of the Russia-Kazakhstan border. Akkuly, the district capital, is to the southwest.
Zhaltyr is part of the Irtysh basin. It lies in a tectonic depression of the Kulunda Plain. Lake Malybay lies close to its northeastern side and red lake Kyzyltuz close to the west. Sharbakty lies to the south, Borli to the northwest, Bargana to the ENE, and Tuz to the SSE.
The lake has an elongated shape, stretching roughly from southeast to northwest for less than . The lake is shallower than its eastern neighbor and its water is harder and has a higher salinity. The shores are flat and marshy. The lake fills mainly with rainfall and groundwater. It freezes at the end of November and thaws in April.
Lake Zhaltyr is surrounded by steppe vegetation. The areas near the shore are used as a pasture for local cattle.