Lake Niegocin (German: Löwentinsee) is a lake in the Masurian Lake District of Poland's Warmian-Masurian Voivodeship. It is the seventh largest lake in Poland, with an area of 26.04 square kilometres (10.05 sq mi). Maximum depth is 39.7 metres (130 ft); average is 9.9 metres (32 ft).