In the context of the current political situation in the country, the relevance of scientific research is due to its extreme importance, seen through the prism of the theoretical and practical significance of law enforcement activities of the Federal security service at various historical stages, and its provision of national security. The scientific novelty of this work is formed from a complex of analytical characteristics of the Federal Security Service activi-ties and comes down to the fact that it presents the special aspects of the professional work of the Federal Security Service, in addition, a comparative assessment of legal norms is carried out. Due to the democratization of Russian society, significant changes are taking place in the law enforcement agencies system. The constitutional consolidation of human and civil rights and freedoms as basic values determines their supremacy in relation to public law values. We emphasize that the Federal Security Service is the leading central body in the system of executive power, whose activities to ensure national security are built taking into account the fundamental principles of legality, respect, observance of human and civil rights and freedoms, conspiracy, in a combination of overt and covert methods and means. We indicate our own position in understanding the essence and characteristics of national security.