Udrzyn [ˈudʐɨn] is a village in the administrative district of Gmina Brańszczyk, within Wyszków County, Masovian Voivodeship, in east-central Poland. It lies approximately 10 kilometres (6 mi) east of Brańszczyk, 21 km (13 mi) north-east of Wyszków, and 71 km (44 mi) north-east of Warsaw.