Mielno is a resort town in Koszalin County, West Pomeranian Voivodeship, in north-western Poland. It is the seat of the gmina called Gmina Mielno. It lies approximately 12 km (7 mi) north-west of Koszalin and 135 km (84 mi) north-east of the regional capital Szczecin. The town has a population of 3,200.