Pustniki [pustˈniki] is a village in the administrative district of Gmina Sorkwity, within Mrągowo County, Warmian-Masurian Voivodeship, in northern Poland. It lies approximately 5 kilometres (3 mi) north of Sorkwity, 9 km (6 mi) west of Mrągowo, and 46 km (29 mi) east of the regional capital Olsztyn.