Miyagi District (宮城郡, Miyagi-gun) is a district located in former Mutsu Province and today's Miyagi Prefecture, Japan. The name of the prefecture was from this district.
The original territory was east–west long from the Ōu Mountains to the Pacific Ocean, including current Sendai, Shiogama, and Tagajō cities. As of 2003, the district has an estimated population of 69,567 and a density of 620.80 persons per km2. The total area is 112.06 km2.