Stary Młyn [ˈstarɨ ˈmwɨn] is a settlement in the administrative district of Gmina Prabuty, within Kwidzyn County, Pomeranian Voivodeship, in northern Poland. It lies approximately 3 kilometres (2 mi) south of Prabuty, 17 km (11 mi) east of Kwidzyn, and 79 km (49 mi) south-east of the regional capital Gdańsk.

For the history of the region, see History of Pomerania.