Jamielnik [jaˈmjɛlnik] is a village in the administrative district of Gmina Nowe Miasto Lubawskie, within Nowe Miasto County, Warmian-Masurian Voivodeship, in northern Poland. It lies approximately 13 kilometres (8 mi) north-west of Mszanowo (the gmina seat), 14 km (9 mi) north of Nowe Miasto Lubawskie, and 71 km (44 mi) south-west of the regional capital Olsztyn.