Sera (世羅郡 Sera-gun?) is a district located in Hiroshima Prefecture, Japan.
As of 2003, the district has an estimated population of 19,213 and a density of 69.04 persons per km². The total area is 278.29 km².
Coordinates: 34°36′54″N 133°00′32″E / 34.615°N 133.009°E