St. Clement's Church (Clemenskirken i Oslo) was one of the Roman Catholic parish churches of Oslo, Norway. Ruins of St. Clement's Church are now exposed and included as part of Middelalderparken in the inner city of Oslo (Gamlebyen). It was located between the former Klemetsallmenningen and Østre strede, south of the former Royal Estate and St. Hallvard's Cathedral. The church was consecrated to St. Clement, who was one of the 1st-century popes. He was martyred by being drowned with an anchor tied around his neck and thus became the patron saint of, among other things, seafarers.