關東平原
Minami Ward is within the Kantō Plain, with a minimum altitude of 2.9 meters and maximum altitude of 16.9 meters above sea level. The Arakawa River and several others drain the area. Minami Ward has three bodies of water: Besshonuma, Shirahatanuma, and Saiko. Approximately 56% of the area was of the ward is residential area and less than 5% was rural; consequently the entire ward was designated a "densely inhabited district" (DID) in 2005.