This paper briefly discuses the Serbian ethnic community in Hungary, emphasizing the change that came about in the 20th century. Namely, the community started to change from an extremely closed, in-group oriented to an open community that allows mixed marriages. Some numerical/statistical data based on censuses and data from the Orthodox Church in Hungary are provided, as well as the Serbian attitudes toward the mixed marriages, and their influences on ethnic identity preservation. Finally, the paper discusses the identity problem of children from such mixed marriages - their self-determination and how other members of the Serbian community relate to them.