Marysin [maˈrɨɕin] is a village in the administrative district of Gmina Lesznowola, within Piaseczno County, Masovian Voivodeship, in east-central Poland. It lies approximately 6 kilometres (4 mi) south-west of Lesznowola, 11 km (7 mi) west of Piaseczno, and 19 km (12 mi) south-west of Warsaw.