The purpose of this article is to fulfil a comparative study of national security legislation, as well as the formation of conceptual foundation for its development and the elaboration of proposals for the improvement thereof with regard to Ukraine. The article analyses in comparative aspect the practice of the Republic of Lithuania as one of the European countries. In the context of globalization, the research focuses on international legal systems of both international and regional levels. The comparative legal analysis of the legal measures to maintain national security revealed similarities in theoretical and methodological approaches. In the study, the author’s definition of national security is given; and a typological model of the concept of national security is formed.