This study is focused on the one of the major problems of the Republic of Moldova: about to the role of the ideology in the post-communist society. This is a comparative study, mentioned of the differences between state ideology and national idea, the role of them in the political life of the state, in the political system as whole. That way, is concerned the role of ideology in the totalitarian system and the role of the ideology in democracy. There are no conditions to create an integrative idea in Republic of Moldova, which will overpass the phases of societal fragmentation. From other point of view, is a comparative study about the ideology situation, the problems of ideological identification in Republic of Belarusi and Russia. State ideology represents a system of ideas and essentials values, which are the core of the Constitution and the state in the matters of government; national idea is the process of becoming and affirmation as a nation. The author examines also the situations when state ideology and national idea have an interconnection. National idea must to correspond to general human values, to the ideals of the developing society, to the vital interests of the Republic of Moldova.