Iisalmi (Finnish: [ˈiːsɑlmi]; Swedish: Idensalmi) is a town and municipality in the region of North Savo in Finland. It is located 87 kilometres (54 mi) north of Kuopio and south of Kajaani. The municipality has a population of 20,330 (30 June 2025), which makes it the second largest of the five towns in North Savo in population, only Kuopio being larger. It covers an area of 872.20 square kilometres (336.76 sq mi) of which 109.22 km (42.17 sq mi) is water. The population density is 26.65 inhabitants per square kilometre (69.0/sq mi). The municipality is unilingually Finnish.
In the 2010s, Iisalmi is known as an export industry town, as well as a significant study town in the region.