Abstract: The subject of this research is the examination of correlation between the processes of interethnic cooperation and social integration of population. The definitions are given to the concepts of “interethnic cooperation”, “social integration”, and “interethnic communication”. It is noted that for Altai Krai, as a polyethnic region of the Russian Federation, these questions are considered as crucial in the area of public administration. Policy of the Russian Federation and its regions is aimed at the development and strengthening of interethnic relations that play an essential role in structuring a harmonious civil society founded on the principles of the equality of nations. The main research method became the questionnaire-based survey, conducted among the population of Altai Krai in 2016, 2017, and 2018. Interethnic cooperation in Altai Krai is characterized with the low level of tension, prevalence of welcoming and friendly relations that contribute to social harmony. The authors determine a significant correlation between the indicators “the level of interethnic cooperation” and “the level of social integration of population”. It must be taken into account in terms of implementation of the state ethnic policy of the region.