Łęg [wɛnk] is a village in the administrative district of Gmina Konstancin-Jeziorna, within Piaseczno County, Masovian Voivodeship, in east-central Poland. It lies approximately 5 kilometres (3 mi) east of Konstancin-Jeziorna, 12 km (7 mi) east of Piaseczno, and 20 km (12 mi) south-east of Warsaw.