Abstract: In this study, the author examines in detail the problem of ensuring the peace and security of mankind through the use of the norms of international humanitarian law and criminal law of the Russian Federation. Ensuring the peace and security of mankind as a task of criminal law and an object of criminal law and international legal protection is closely linked to the provisions of international humanitarian law, since the rules of warfare established by it, if violated, threaten the peaceful coexistence of peoples and States. In this regard, it seemed appropriate to the author to consider the history of the development of the protection of peace and security of mankind through the prism of the origin of legislation on war. The author turns to history and, based on historical facts, establishes the periodization of the development and formation of the prohibition of an act of aggression. The author also developed his own concept of "peace" for the purposes of applying Chapter 34 of the Criminal Code of the Russian Federation.  In preparing this study, the author used such methods as formal legal, historical, comparative, as well as methods of analysis, induction and deduction. The conducted research allowed us to come to the following conclusions: legislation on ensuring the peace and security of mankind began its formation in the early Middle Ages and reached its peak after the end of World War II; peace is a state in the absence of the use of armed forces of states against the sovereignty, territorial integrity or political independence of each other, or armed organized non–state groups against Russian legislation reflects a number of prohibitions on the commission of crimes against the peace and security of mankind, but the very elements of these crimes are imperfect and need to be improved in terms of consolidating the basic definitions. In this regard, it seems advisable to develop and approve a resolution of the Plenum of the Supreme Court of the Russian Federation or a separate Federal law that would address the main problematic issues that cause difficulties in correctly classifying crimes against the peace and security of mankind.

Keywords: the composition of the crime, aggression, criminal law, rehabilitation of Nazism, genocide, aggressive war, international law, ensuring security, Ensuring peace, human security