Smardzewo [smarˈd͡zɛvɔ] is a village in the administrative district of Gmina Sochocin, within Płońsk County, Masovian Voivodeship, in east-central Poland. It lies approximately 5 kilometres (3 mi) west of Sochocin, 8 km (5 mi) north of Płońsk, and 68 km (42 mi) north-west of Warsaw.