Rostki [ˈrɔstki] is a village in the administrative district of Gmina Nowe Miasto, within Płońsk County, Masovian Voivodeship, in east-central Poland. It lies approximately 6 kilometres (4 mi) south-east of Nowe Miasto, 21 km (13 mi) east of Płońsk, and 50 km (31 mi) north-west of Warsaw.