Kuusamo is a town and municipality in Finland. It is located in the Northern Ostrobothnia region. The municipality has a population of 15,209 (31 December 2020) and covers an area of 5,808.92 square kilometres (2,242.84 sq mi) of which 830.81 km² (320.78 sq mi) is water. The population density is 3.06 inhabitants per square kilometre (7.9/sq mi).

The municipality is unilingually Finnish.

Kuusamo is a major center for winter sports and receives approximately a million tourists every year. One of the largest ski resorts in Finland, Ruka, is situated in Kuusamo. Ruka is also the host of many international competitions in ski jumping, cross country skiing and Nordic combined. The 2005 World Championships of Freestyle Skiing was held in Kuusamo. Kuusamo Airport is located 6 kilometres (4 mi) north-east from Kuusamo town centre.

The city lies on a roughly 250-meter-high plateau, from which the waters flow in five directions. In the area of Kuusamo there are many hills (Finn. vaara) and fells (Finn. tunturi). The highest elevations are Valtavaara (492 m), Kuntivaara (481 m), Iivaara (469 m) and Rukatunturi (490 m), the site of the Ruka ski center.

Ninety percent of the land area is forested. The forests consist mainly of pine trees (70%) with some spruce (20%) and deciduous trees (10%). 801 km² (309 sq mi) or 14% of the area of Kuusamo is covered by water. The largest of the 166 lakes in the area are Joukamojärvi, Kiitämä, Kitka, Kurkijärvi, Kuusamojärvi, Muojärvi and Suininki. Rivers in the area include Oulankajoki, Kitkajoki, Kuusinkijoki and Pistojoki flowing eastward to the White Sea and Iijoki westward to the Gulf of Bothnia.

The 270 km² (100 sq mi) area of Oulanka National Park is shared between northern Kuusamo and neighboring Salla municipality. The landscape is dominated by pine forests, Oulankajoki river and its side branches with their sandbanks and rapids, and in the northern part vast marsh areas. In the wilderness live 30 species of mammals and 120 species of birds, including brown, stone and white-tailed eagle. Wolves and lynxes are rare. Rapids in Oulankajoki include Kiutaköngäs, Taivalköngäs, Jyrävä, Niskakoski and Myllykoski. Near the southern border with Suomussalmi is the canyon lake Julma Ölkky with up to 50 m (160 ft) high cliffs.