Multinational corporations are one kind of economical organization which blend economic and political behavior,and it is an agent with multi-dimension behavior.The fundamental difference between multinational and inner enterprises is that multinational corporations make the imperfection of economic and political market inside,and the imperfection is beyond national boundaries.In the international relations the political factor of multinational corporations sorely influences the relation between the multinational corporations and national government and their respective behavior manners.So we must analyze political behavior,motivation,mode function of multinational corporations with economic theory.