Ulken Azhbolat (Kazakh: Үлкен Әжболат; Russian: Большой Ажбулат, Bolshoy Azhbulat) is a bittern salt lake in Uspen District, Pavlodar Region, Kazakhstan.

[4] Lake Ulken Azhbolat is an endorheic lake located in the Kulunda Steppe, southern part of the West Siberian Plain, west of the Russian border.

The Burla river flows into the eastern lakeshore.

[3] In years of adequate rainfall the river reaches the lake, but in dry years it ends in Lake Bolshoye Topolnoye, located 22 kilometers (14 mi) to the east, on the other side of the Kazakhstan–Russia border.

Lake Shagan straddles the international border 17 kilometers (11 mi) to the northeast, Ulken Tobylzhan lies 45 kilometers (28 mi) to the south, lake Burlinskoye 57 kilometers (35 mi) to the ESE, lake Bolshoye Yarovoye 77 kilometers (48 mi) to the southeast and lake Kyzyltuz 60 kilometers (37 mi) to the northwest.