Zajączki [zaˈjɔnt͡ʂki] is a village in the administrative district of Gmina Lubomino, within Lidzbark County, Warmian-Masurian Voivodeship, in northern Poland. It lies approximately 28 kilometres (17 mi) south-west of Lidzbark Warmiński and 32 km (20 mi) north-west of the regional capital Olsztyn.

Before 1772 the area was part of Kingdom of Poland, and in 1772–1945 it belonged to Prussia and Germany (East Prussia).