Piaseczno County () is a unit of territorial administration and local government (powiat) in Masovian Voivodeship, east-central Poland. It came into being on January 1, 1999, as a result of the Polish local government reforms passed in 1998.
Piaseczno County is a part of Poland's administrative structure, serving as a local unit of governance (powiat) within Masovian Voivodeship. It was established on January 1, 1999, following the Polish local government reforms of 1998.