Piastowo [pʲasˈtɔvɔ] is a village in the administrative district of Gmina Lubaczów, within Lubaczów County in the Subcarpathian Voivodeship. It is in south-eastern Poland, near the border of Ukraine. Piastowo lies approximately 6 kilometres (4 mi) east of Lubaczów and 87 km (54 mi) east of the regional capital Rzeszów.