Pfarrkirche St. Mauritius, Catholic parish church in Appenzell, Switzerland.

Pfarrkirche St. Mauritius is the Catholic parish church of Appenzell, dedicated to Saint Maurice, patron saint of the canton. Its present appearance comes from a classical nave built in 1824–1825, while the late-Gothic choir and tower were kept. Inside, the 1890–1892 Neo-Rococo remodelling survived the 2018–2019 renovation, and the high altar dates from 1622.

The first church on this site was built around 1068/1069 and consecrated by Bishop Thietmar of Chur at the request of Bishop Rumold of Konstanz. In 1248 the parish was incorporated into the Abbey of St. Gallen. The classical nave was rebuilt between 1824 and 1825, while the late-Gothic choir and tower were kept. The high altar dates from 1622.

The parish was the mother church of the inner Rhoden and, after the 1597 division of the canton, of the inner part of Appenzell Innerrhoden. Its territory shrank as Gonten and Haslen became separate parishes in the 17th century and the chaplaincies of Brülisau, Eggerstanden, Schwende and Schlatt were founded; Brülisau became a parish in 1845, Schwende in 1914. Saint Maurice is the canton's patron saint.

The building is located at Hauptgasse 2 and is accessible during regular services, including sung masses and special celebrations on religious holidays. Visitors should be aware of service times and choose appropriate clothing when entering during worship.

The high altar dates from 1622 and survived the 1824–1825 rebuilding of the nave, which kept the late-Gothic choir and tower. The neo-Rococo interior of 1890–1892 largely survived the 2018–2019 renovation. Since 1971 the church has held Switzerland's highest heritage protection status.