The museum building is one of the most distinctive modernist creations of 1960’s Finland. The simple and stern, but equally exciting and unique form attracts those interested in architecture from all around the world. The building was inaugurated in 1968 and was designed by architect Woldemar Baeckman, whose designs can be found in many buildings around the campus as well. The museum building is included in the Docomomo register selection of modern Finnish architectural masterpieces.

The low profile of the museum building contrasts itself clearly among the other buildings around it, which are from the 19th century. The building has two stories, one of which is underground and houses exhibition and archive spaces along with a lecture hall. The museum is built around a concert hall known as the Sibelius-hall. Next to the hall lies a square shaped atrium, surrounded by offices and other showrooms. The original interior design was made by decorator Carin Bryggman, and the atrium was designed by landscape architect Marja-Liisa Rösenbröjer. The interior design was later complemented by decorator Assi Sandelin (2002) and the atrium was redesigned by architect Pia Sabelström (2019). The atrium is used as a concert venue in the summer and is open to all visitors.