The article is devoted to a comprehensive analysis of the problems of social security of internally displaced persons in Ukraine under martial law. The legal foundations of social protection of IDPs are studied, the main regulatory legal acts regulating this area are analyzed, and key problems of their practical implementation are identified. Particular attention is paid to the analysis of changes in legislation caused by the full-scale armed aggression of the Russian Federation against Ukraine. Ways of improving the social security system of IDPs and increasing the effectiveness of state policy in this area are proposed.