Kajaani (Kajana in Swedish) is a municipality of Finland.

It is located in the province of Oulu and is part of the Kainuu region. The municipality has a population of 35964 and covers an area of 1369,13 kmē of which 212,04 kmē is water. The population density is 30,975 inhabitants per kmē.

The municipality is unilingually Finnish.

See also: Municipalities of Oulu