Minamiaizu (南会津郡, Minamiaizu-gun) is a district located in Fukushima Prefecture, Japan. It makes up the southern third of the Aizu region in western Fukushima Prefecture.
As of 2003, the district has an estimated population of 33,533 and a density of 14.32 persons per km². The total area is 2,341.64 km². It is the least populated part of Aizu.
Coordinates: 37°09′22″N 139°26′24″E / 37.156°N 139.44°E / 37.156; 139.44