Hiroo (広尾郡, Hiroo-gun) is a district located in Tokachi Subprefecture, Hokkaido, Japan.
As of 2004, the district has an estimated population of 16,735 and a density of 10.80 persons per km2. The total area is 1,550.06 km2.
42°28′12″N 143°10′12″E / 42.47000°N 143.17000°E