St. Joseph's Church, Catholic church building in Rheinfelden, Switzerland.

St. Joseph's Church is the Roman Catholic parish church of Rheinfelden, built in 1949 to plans by architect Alois Moser and consecrated in 1950. It stands at Hermann-Keller-Strasse 8, east of the old town, and was built of wood, natural stone and plaster under a tiled roof. A free-standing bell tower 30 metres high rises on the right, holding five bells; a baptismal chapel projects from the left side of the main entrance.

The first St. Joseph's Church was built in 1882 to plans by Joseph Meyer of Basel in neo-Gothic style, after the Roman Catholic parish separated from Rome in 1872/1873 and left St. Martin's to the Christian Catholic community. A tower by Meyer replaced the roof turret in 1898. The present church was designed by Alois Moser of Baden, approved in 1945, begun in 1948 on the initiative of the "Bettelpfarrer" Felix Schmid, and consecrated on 1 October 1950 by Bishop Franziskus von Streng.

The church serves as a gathering place for the local Catholic community and hosts regular services that draw parishioners from the surrounding area. It remains central to the spiritual life of Rheinfelden.

The church stands at Hermann-Keller-Strasse 8, east of Rheinfelden's old town, with the parish house beside it and the old town park diagonally opposite. A flight of steps leads up to the church square in front of the main entrance. The free-standing bell tower, 30 metres high, is on the right side; the baptistery chapel projects on the left of the main portal.

The five bells, cast by Josef Pfunder in Vienna, arrived on 15 September 1950 and weigh 8000 kg in total. When they were hoisted the next day, the schoolchildren of Rheinfelden were allowed to help. The tower's sound windows have wooden louvres so the ringing carries far but is not too loud close by.