The internationalization of national constitutions includes an eventual unification of constitutional rules deemed necessary to intensify international relations. So, in a broader way it is invoked the impact of international law and international relations on constitutional law. The result of the internationalization of national rights is a progressive harmonization of concepts and legal rules. In the current state of international law, constitutions' internationalization corresponds a concrete impact of international law on constitutional norms. The current trend of constitutions is to regulate in a more accurate and comprehensive way the relations between the state and international law. International law does not require any particular form of the conclusion of international treaties. In intensification of international relations, international conventions and integration of states in international organizations, the Parliament carries important consequences for both on normative function and the control function. Such legislative activity is guided by international treaties concluded by the state. While the executive and the legislative are involved in the development of international law, the jurisdictional power intervenes to reconcile domestic and international legal norms. States do not devote supremacy of international law over their constitution. Because international treaties to be part of the national legal order is not enough that the procedure for concluding treaties to be respected. It is also necessary that treaties do not contravene fundamental state constitutional principles of human rights and the relationship between public authorities. The control of international treaties' constitutionality can be mandatory or optional. In the process of ratification of the treaty on EU European constitutional courts tend to create a similar design to establish the limits of European integration. In reality, the issue of constitutionality of international treaties control is a political issue and it is difficult to apply legal principles purely political matters. There are three categories of states in the aspect of national courts on constitutional regularity control concluding treaties.