Iwamizawa (岩見沢市, Iwamizawa-shi?) is a city located in Sorachi, Hokkaidō, Japan.
On March 27, 2006 the town of Kurisawa, and the village of Kita, both from Sorachi District, Sorachi Subprefecture, have merged into Iwamizawa.
As of 2009, the city has an estimated population of 90,969 and the density of 189 persons per km². The total area is 481.10 km2 (186 sq mi).
The city was founded on April 1, 1943. Its sister city is Pocatello, Idaho, United States. Youth delegates are often sent from one to the other.