Gostomin [ɡɔsˈtɔmin] is a village in the administrative district of Gmina Ojrzeń, within Ciechanów County, Masovian Voivodeship, in east-central Poland. It lies approximately 5 kilometres (3 mi) north-west of Ojrzeń, 12 km (7 mi) south-west of Ciechanów, and 74 km (46 mi) north-west of Warsaw.