Kiersztanowo [kʲɛrʂtaˈnɔvɔ] is a village in the administrative district of Gmina Grunwald, within Ostróda County, Warmian-Masurian Voivodeship, in northern Poland. It lies approximately 19 kilometres (12 mi) south-east of Ostróda and 35 km (22 mi) south-west of the regional capital Olsztyn.