The Sara Didrichsen Art Museum is an art museum in Pietarsaari, especially known for its exhibitions of modern art. The museum was founded in 1965 and is named after the mayor of Pieterssaar, Sara Didrichsen.
The museum's collections consist mainly of modern art and include many important Finnish artists, such as Akseli Gallen-Kallela, Helene Schjerfbeck, Eero Järnefelt and Reidar Särestöniemi. The museum also exhibits works of foreign modern art.
The museum building is a traditional wooden house, built in 1913, whose historic atmosphere provides an interesting backdrop for modern art. Inside the museum, there are several different exhibition spaces that allow for a variety of exhibitions.
The Sara Didrichsen Art Museum has constantly changing exhibitions and events. The museum also organises various art education programmes and workshops, especially for children and young people.