The Croatian Democratic Union (Croatian: Hrvatska Demokratska Zajednica, HDZ), is a Croatian political party.

It was founded in the early 1990s by Franjo Tudjman and led by him until his death. Under him it ruled Croatia from 1990 to 1999. It then lost elections to the Social Democratic Party of Croatia. In 2003 it, under new leader, Ivo Sanader, won parliamentary elections.

See also: List of political parties in Croatia, Politics of Croatia

There is also a Croatian Democratic Union in Bosnia.