thumb|200px|The area of Kamiiso District in Oshima Subprefecture.
is a district located in Oshima Subprefecture, Hokkaido, Japan.
As of 2004, the district has an estimated population of 48,470 and a density of 71.18 persons per km<sup>2</sup>. The total area is 680.95 km<sup>2</sup>.
Towns
- Kikonai
- Shiriuchi
Merger
- On February 1, 2006, the town of Kamiiso merged with the town of Ōno, from Kameda District, to form the new city of Hokuto.