Leśna [ˈlɛɕna] (German: Marklissa) is a town in Lubań County, Lower Silesian Voivodeship, in south-western Poland, close to the Czech border.

The town is situated north of the Jizera Mountains on the left banks of the Kwisa River, the eastern edge of the historic Upper Lusatia region.

Leśna Castle, erected on the border with the Polish Duchy of Silesia about 1.5 kilometres (0.9 miles) southeast of the town, was first mentioned in a 1247 deed.

A first town layout was abandoned in 1434 upon devastations by the Hussite Wars, a flood and a fire, and rebuilt at its present location further south on the route from Frýdlant to Lubań.

After World War II the town, located east of the Oder-Neisse line, was ceded to the Republic of Poland according to the 1945 Potsdam Agreement.