The aim of this article is to show the role of Catholicism in shaping the Slovak national identity. The thesis was put forward that the Catholic confession was very clearly present in the history of the Slovak state and nation and had a significant impact on the formation of the national identity, while the shape of the state-church relations is determined by socio-political factors and historical tradition. However, Catholicism is not the only religion in this regard, as it is impossible to ignore the importance of the Greek Catholic Church, the Evangelical-Augsburg Church and the Orthodox Church. Contemporary Europe is becoming more and more secularized, and the condition of Christianity, especially Catholicism, is getting weaker. Slovakia is among the few countries in the European Union that support this process, along with Poland, Croatia and Malta.