Unresolved problems of social and economic development of Ukraine, exacerbated by critical negative consequences of military aggression and political instability, are accompanied by deep socio-economic contradictions and aggravation of large-scale social problems. At the same time, the qualitative system of social security, characteristic of the EU, is not formed. As a result, negative phenomena and trends are accumulated in social sphere there that manifest themselves in the critical deformations of social development, with the formation of threats of degradation and depopulation, the increase of environmental problems, deterioration of social structure, weakening of social guarantees of human rights that are evidenced and confirmed by mass and active labour migration of the Ukrainians abroad. Ensuring Ukraine’s social security objectively requires an in-depth study based on a systematic approach, applying EU principles, provisions, practices, and standards. The purpose is to substantiate approaches and means of convergence of social security of Ukraine and the EU and develop recommendations for the improvement of migration policy. Methodology. As the methodological basis of the study, theories of socio-economic growth, modern concepts of institutional and structural economic reforms have been worked out, methods of statistical, structural-functional, and system analysis, grouping have been applied. Results. The imbalances of social security of Ukraine and the EU have been determined according to the following components: labour market and employment of population; reproduction of population and labour potential of the state; migration and food security. Areas of accelerated asymmetry increase in the social development of Ukraine and the EU, which serve as a key factor in “pushing out” the population and high rates of labour migration from Ukraine to the EU Member States, have been identified. Strategic approaches and means of equalizing critical deformations and convergence of the system of social security of Ukraine in the process of integration into the EU have been determined; tools for improving the state migration policy have been developed, which implementation would result in improvement of the systemic and structural characteristics of labour potential migration. Conclusion. The study results obtained represent the existence of significant disparities in key indicators and components of the social security system of Ukraine and the EU. Low level of living standards and social protection of population serves as a factor in increasing the scope of external labour migration and, correspondingly, a critical weakening of human and labour potential of the state. Tools and means of the state policy of convergence of the social security system of Ukraine and the EU should focus on achieving the goal of systemic development of human capital and be implemented in the following directions: ensuring demographic security, upgrading health care system, renovating the quality of education, preserving cultural values, establishing a competitive labour market, improving housing affordability, social infrastructure development, systemic social insurance of population.