The article deals with the analysis of social justice as a universal value that determines the evaluation of social practices in all the spheres of social life. But the study of such an evaluation of society in the sphere of interethnic relations is faced with a number of theoretical problems. The authors show that when evaluating interethnic relations in accordance with the criterion of social justice, due to the ambiguous interpretation of their meaning, it is necessary to rely on an interdisciplinary approach. An important area of this analysis is the correlation of the theoretical understanding of ethnicity and the practice of state building in the context of the cultural diversity of the population. Two strategies for achieving social justice in the sphere of interethnic relations are shown: the building of the SU ethno-nations and the building of the RF nation with securing civil rights in the sphere of the implementation of ethno-cultural identity and providing conditions for the development of ethno-cultural diversity.