This article deals with the problem of the religion of the ethnic Germans in Hungary. It is assumed that Catholicism serves as an important item of the ethnic identity of this minority from diachronic as well as from synchronic perspective. Catholic religion has the historic function to help the ethnic survival. Religion has a very important role to divide and to unite ethnic minorities and the majority. A great deal of the Germans settled in Hungary in the 18th century is Lutheran. Catholic and Lutheran Germans are divided by their religion, which can be seen at their marriage customs, too. Since the Hungarian majority is also Catholic, both Germans and Hungarians have the cult of the Blessed Virgin, who is held by the Hungarian believers as Patrona Hungarica. With the help of a shared religion with the majority, they could develop a basis for national feelings and for assimilation, too.