South Lake) is an administrative region in the Federal District in Brazil.

It is located on the south side of the eastern shore of Lake Paranoá, opposite of Brasília and Lago Norte.

The Presidente Juscelino Kubitschek International Airport is located in the southwesternmost edge of the region.

Lago Sul is part of the Brazilian Highlands, with large amounts of cerrado vegetation.

Lago Sul has a tropical savanna climate (Aw in the Köppen Classification).