Abstract: The subject of the study is ethnic-and-social causes of emergence of unrecognized States in the post-Soviet space. The national policy pursued by the Russian Empire and later by the Soviet Union has sown the seeds of ethnic and political conflicts in the post-Soviet space. The process of ethnic mobilization, which is based on the problem of ethnic identity of different cultures living in the territory of the post-Soviet space, started after the collapse of the Soviet Union. It resulted in formation of unrecognized States in Transnistria and the Caucasus, the emergence of which is conditioned upon the occurrence of ethno-political conflict. The methods of historical and political sciences, in particular, monographic, descriptive and comparative historical methods were used in the study. The novelty of the study lies in discovery of the prerequisites for the emergence of ethnic and political conflicts in the post-Soviet space as a result of the research of the impact of the problems of national identity of Nations living in the post-Soviet space. The study revealed the peculiarities of the national policy of the Russian Empire and the USSR, which inspired the development of ethnic tension after the collapse of the USSR. The author investigated the mechanism of ethno-political conflicts in the post-Soviet space.