The oldest works in the collection are two portraits painted by Oulu-born artist Isaac Wacklin in 1755. An important artist in the collection is Vilho Lampi, a painter from Liminka. Thanks to purchases and donations, the museum has the largest Vilho Lampi collection in Finland, 80 works.

Special themes of the collection are self-portraits, the northern dimension and naïve art, the accumulation of which began with a donation from the Heinänen Art Foundation in 1987. Collection acquisitions are also determined by research and exhibition needs. The museum does not have a permanent main exhibition, but works from the collection are displayed in collection exhibitions and other exhibitions produced by the museum. Artworks are also loaned to other museums for exhibitions.