Zaszków [ˈzaʂkuf] is a village in the administrative district of Gmina Nur, within Ostrów Mazowiecka County, Masovian Voivodeship, in east-central Poland. It lies approximately 10 kilometres (6 mi) south-east of Nur, 42 km (26 mi) south-east of Ostrów Mazowiecka, and 109 km (68 mi) north-east of Warsaw.