Ojrzeń [ˈɔi̯ʐɛɲ] is a village in Ciechanów County, Masovian Voivodeship, in east-central Poland. It is the seat of the gmina (administrative district) called Gmina Ojrzeń. It lies approximately 13 kilometres (8 mi) south-west of Ciechanów and 69 km (43 mi) north-west of Warsaw.