thumb|200px|Shizunai District in Hidaka Subprefecture before merging with Mitsuishi District in 2006.
was a district located in Hidaka Subprefecture, Hokkaido, Japan.
In 2004, the district had an estimated population of 22,581 and a density of 28.17 persons per km<sup>2</sup>. The total area was 801.51 km<sup>2</sup>.
On March 31, 2006, Shizunai District merged with Mitsuishi District to create the newly created Hidaka District. Mitsuishi District and Shizunai District were both dissolved with this merger.
Towns and villages
- Shizunai