The Museum of Polish Reformation in Mikołajki was established in 1973.
At first, the exhibition was located in a Church, and since 2002, the museum is in a new building at the Lutheran Parish in Mikołajki (Plac Kościelny 4). The collection includes important works of Polish literature and printing in Mazury until 1945, and the valuable prints, documents, and photographs related to the Reformation in Poland and Europe.