Słomczyn [ˈswɔmt͡ʂɨn] is a village in the administrative district of Gmina Konstancin-Jeziorna, within Piaseczno County, Masovian Voivodeship, in east-central Poland. It lies approximately 4 kilometres (2 mi) south-east of Konstancin-Jeziorna, 11 km (7 mi) east of Piaseczno, and 21 km (13 mi) south-east of Warsaw.