The processes of forced internal migration, which became significant in 2014 as a result of the armed conflict in the east of the country, caused significant demographic and social changes in the regions performance. Particularly large changes have been taken place in the areas directly adjacent to the joint forces operation zone. The study is devoted to the research of the impact of the described processes on certain aspects of social and economic security of the regions. Impact assessment was performed on the basis of cluster analysis. In particular, the author constructed a neural network such as the Kohonen map. The model divided the neural sample from 25 regions (24 regions and the city of Kyiv) into six clusters according to the level of four indicators of social and economic security. This allowed assessing the impact of forced internal migration on some aspects of social and economic security of the regions. Based on the obtained map, it has been depicted that Donetsk and Luhansk regions, which directly border the joint forces operation zone, had a dramatic increase in the demographic burden and unemployment rate during the study period. The obtained results allowed assessing the impact of the processes of forced internal migration on the dynamics of certain indicators of social and economic security of the territories.