Balkhash, or Balqash, Lake, a lake in Kazakhstan. It is in the southeastern part of the country, about 100 miles (160 km) west of the Chinese border and 600 miles (965 km) east of the Aral Sea. The lake is 375 miles (600 km) long and 15 to 55 miles (25 to 90 km) wide. Its area is 6,900 square miles (17,870 km2).

Lake Balkhash is frozen five months of the year. The Ili is the chief river flowing into the lake. There is no outlet. Near the Ili's mouth the water is fresh, but it becomes increasingly salty toward the east. There is commercial fishing in the lake.