The Catholic Church in Lithuania (Lithuanian: Katalikų Bažnyčia Lietuvoje) is part of the worldwide Catholic Church, under the spiritual leadership of the Pope in Rome. Lithuania is the world's northernmost Latin Catholic-majority country. Pope Pius XII gave Lithuania the title of "northernmost outpost of Catholicism in Europe" in 1939. The Vilnius Cathedral is the most important Catholic Church in Lithuania, which was previously used for the inauguration ceremonies of Lithuanian monarchs with Gediminas' Cap, while in modern times it is a venue for masses dedicated to the elected Presidents of Lithuania after their inauguration ceremonies and giving of oaths to the Nation in the Seimas Palace.
Among the Baltic states, Lithuania is the country with the highest percentage of Catholic population. Almost three-quarters (74.19%) of Lithuania's population self-identified as Catholics in the 2021 census. The country is divided into eight dioceses including two archdioceses and a military ordinariate.