Lower Lusatia (German: Niederlausitz, Lower Sorbian: Dolna Łužyca, Upper Sorbian: Delnja Łužica, Polish: Łużyce Dolne, Czech: Dolní Lužice) is a historical region in Central Europe, stretching from the southeast of the German state of Brandenburg to the southwest of Lubusz Voivodeship in Poland. Like adjacent Upper Lusatia in the south, Lower Lusatia is a settlement area of the West Slavic Sorbs whose endangered Lower Sorbian language is related to Upper Sorbian and Polish.
The sparsely inhabited area within the North European Plain (Northern Lowland) is characterised by extended pine forests, heathlands and meadows. In the north it is confined by the middle Spree River with Lake Schwielochsee and its eastern continuation across the Oder at Fürstenberg to Chlebowo. In the glacial valley between Lübben and Cottbus, the Spree River branches out into the Spreewald ("Spree Woods") riparian forest. Other rivers include the Berste and Oelse tributaries as well as the Schlaube and the Oder–Spree Canal opened in 1891.