Flesze is a village in the administrative district of Gmina Grajewo, within Grajewo County, Podlaskie Voivodeship, in north-eastern Poland. It lies approximately 5 kilometres (3 mi) west of Grajewo and 79 km (49 mi) north-west of the regional capital Białystok. A small pond lies at the center of the village, which, during the season, is a popular destination for local fishermen.