The scientific significance and timeliness of studying the social determination of the process of ethnic integration, adaptation and socialization of the migrating population in the cross-border regions of Russia is determined by the global processes of social mobility growth due to the economic and political heterogeneity of the development of the territories of the Russian Federation and the world. Optimization of migration policy that removes bureaucratic obstacles to migrants, causes social security, harmonious combination of inclusion of non-ethnic population with careful preservation of its national heritage, continues to be one of the most important scientific applications, relevant for almost all countries of the world and especially for modern Russia.The purpose of the analysis presented in the article was to assess the opinions of the expert community of the six regions of the Russian border region on the importance of migration processes, its impact on all components of life in the region, the identification of positive and negative consequences, the role of diasporas in the integration of migrants, etc. The presented results are based on the synthesis of modern sociological theories in the study of migration processes, as well as the applied theory of socially determined migration policy developed by modern Russian sociologists. Conclusions about the role of migration processes in the regions are made, their specificity is determined, General and special in the experts' assessments of various manifestations of adaptation and socialization of migrants in the studied border areas of the Russian Federation are highlighted. The scientific novelty of the proposed results lies in the study of the integration and adaptation potential of migrants in the context of the expert opinion of persons on whom the intensification of migration policy optimization in cross-border regions primarily depends. The practical significance lies in the possibility of using the specifics of the identified aggregate expert opinion for effective social management in the field of migration policy.