旧天主教会（Old Catholic Church），也称作老天主教会、古天主教会、旧公教会、老公会等，是信奉基督宗教的教会。许多教会为使用德语的平信徒和教士，1870年代从罗马天主教会独立而出，导因是1869年–1870年的第一次梵蒂冈大公会议所公布的信条─教宗无谬论。「旧天主教」这项名称最早在1853年用以描述乌得勒支总主教的教会肢体，他们是不处在教宗权威之下的公教会。欧洲大陆的旧天主教会通常都是乌得勒支协进会的成员。现今在英国以及北美有使用英语的旧天主教会，他们与乌得勒支协进会并没有「完全共融」。斯洛伐克的旧天主教会是欧洲大陆的旧天主教会的一项示范，他们主动加入乌得勒支协进会。

An Old Catholic Church originated with groups which separated from the Roman Catholic Church over certain doctrines, primarily concerned with papal authority. These churches are not in full communion with the Roman Catholic Church; member churches of the Union of Utrecht of the Old Catholic Churches (UU) are in full communion with the Anglican Communion; and some are members of the World Council of Churches. The formation of the Old Catholic communion of Germans, Austrians and Swiss began in 1870 at a public meeting held in Nuremberg under the leadership of Ignaz von Döllinger, following the First Vatican Council. Four years later episcopal succession was established with the consecration of an Old Catholic German bishop by a prelate of the Church of Utrecht. In line with the "Declaration of Utrecht" of 1889, they accept the first seven ecumenical councils and doctrine formulated before 1054, but reject communion with the pope and a number of other Roman Catholic doctrines and practices. The Oxford Dictionary of the Christian Church notes that since 1925 they have recognized Anglican ordinations, that they have had full communion with the Church of England since 1932 and have taken part in the ordination of Anglican bishops. Some orders are still recognized by the Roman Catholic Church although not any women priests.