The article presents theoretical reflections on the phenomenon of inter-ethnic tension, which characterizes relations between ethnic groups that are in contact with each other. As a rule, the studies of inter-ethnic tension define it as a state of group consciousness of two or more ethnic groups with manifest aversion or hostility to each other. Inter-ethnic tension is often bolstered by emerging ethnic consciousness. The group consciousness revives the complexes of the “people that endured suffering” and that have “legitimate rights” ought to be recognized by the authorities and other ethnic groups. The rise of ethnic consciousness leads to a situation when most social problems are viewed as having ethnically- based causes. Among other ethnic groups ethnic consciousness chooses a “culprit” that has to amend for the past grievances. Inter-ethnic tension is often used by various social forces as an effective means of mobilization that assists in defending the economic and political interests of one of the factions of local or federal elites. In sociology, the problem of inter-ethnic tension is regarded as mobilization affected by economic, social and cultural factors. Aversive attitudes pose as one of the significant factors contributing to inter-ethnic tension. Aversive attitudes presuppose a latent rejection of an ethnic group in the form of avoidance of contacts with it and attributing it with negative characteristics. Research results show that the process of attribution is influenced by practices in which large groups of the population are involved, as well as by social relations in the society. Aversive attitudes are resilient to change and can persist even in a close ethno-contact situation with ethnic groups finding themselves in close relations. In a situation of social conflict aversive attitudes mutate into violence-laden attitudes. The state of inter-ethnic tension is dependent on many factors embedded in culture, social and economic relations. Therefore the study of the phenomenon requires a complex approach that includes a sum of circumstances in which ethnic groups find themselves.