Borek [ˈbɔrɛk] is a village in the administrative district of Gmina Czerwin, within Ostrołęka County, Masovian Voivodeship, in east-central Poland. It lies approximately 3 kilometres (2 mi) west of Czerwin, 18 km (11 mi) south-east of Ostrołęka, and 94 km (58 mi) north-east of Warsaw.