Abstract: The article is devoted to the study of the features of the legal regulation of the Institute of territorial defense at certain stages of the historical development of Russia. The object of the study is a comparison of conceptual approaches to determining the content of territorial defense, its organization and functioning. The subject of the study is a system of legal sources that, in certain historical periods, establish requirements for the organization, deployment and conduct of territorial defense, regulating the functions of military administration bodies, state authorities and local self-government bodies in the field of territorial defense. The scientific novelty of the presented work consists in the preparation of a comprehensive analysis of the nature of changes in views and approaches to the organization of territorial defense, the study of the evolution of the legal understanding of the institute of territorial defense, reflected in scientific works, based on the results of a comparison of documents of the military administration of the Soviet state and modern Russia. The solution of research tasks was made possible through the use of an appropriate system of methods, the basis of which is comparative legal, historical-legal and other methods of scientific cognition. Based on the analysis of the sources of military legislation, the author comes to the conclusion that in various historical conditions, the organizational and functional content of territorial defense differed, this differentiation was reflected in the legal documents of the military administration bodies.