This article speaks about the genesis and functional rules of international system and european subsystem. The international system and its continental (geographical) manifestation under european subsystem, that in this study is European Union(EU), have a different genesis and a functional way, though the both are „the produce” of the same continent – Europe. The genesis and functional rules of both is analysed having as a theoretical- methodical suport systematic theories developed in international relations paradigms. The genesis of those two systems differ from the systematical component having a generator role – in one case the economic basis in other one the politic suprastructure. Its function differ trough coercion role and distribution of the welfare in the system. Namely the function make tempted the european subsystem for the other states, included the Republic of Moldova.