The development of society provides for constant changes in the axiological foundations of legal regulation within the State. The Constitution, on the other hand, acts as a fundamental document that forms the basis of relations between the cells of society, taking into account current values. Based on the study of the world experience in constitutional construction, a conclusion is made about the presence of a general trend in the replenishment of the value catalogue of Constitutions, taking into account the historical experience accumulated by States and national priorities. The article discusses the process of improving the organization of the State power system in the context of constitutional reforms on the example of Russia and others Commonwealth of Independent States (CIS) countries and some European countries in recent years. It concludes that the conditions improving the efficiency and consistency of the entire public administration system in the countries under consideration have unconditionally formed due to ongoing constitutional reforms that have updated the system of social relations. The subject of the study are the constitutional amendments in the countries under study, mainly in the context of changes in the model of functioning and interaction of the higher State authorities.