The Museum in der Schlosskirche (Museum in the Castle Church) is a museum in Saarbrücken which houses a rich collection of sacred art from the Middle Ages to the 19th century. Its seat, the Castle Church, is one of the most important sacred buildings of the Middle Ages in the city of Saarbrücken. It is a late Gothic church that stands on the remains of an ancient 13th century chapel. In the mid-16th century the church became an independent parish and in 1575 it became a Protestant church. Since 1651, the castle church has been the burial place of the counts and princes of Nassau-Saarbrücken. It was destroyed twice, first in 1677 during the Franco-Dutch War and again in World War II. In 2004, following restructuring and reconstruction measures, the church was rearranged as a museum space.

It preserves a rich collection of Sacred Art. Besides this, the church is very famous for the rich programming of contemporary art exhibitions and events. It is also used as a concert hall by the Saarsbrücken University of Music.