Before the World War II, the German political party system focused on ideology and doctrine. However, this tendency made shift soon after war. The parties of the Federal Republic Germany concentrated much on practical matter of organizing government. Since its political decisions are almost made by political parties, the West Germany's political system has been termed ”party-state” Then, after unification, what is the likely future of the German political party system? Will it continue or change the established party system that has been stable in the former West Germany? Applying the theory of Cleavage Model, Functional Model, this paper shows that the united Germany's party system will continue in the foreseeable future.