How does IR theory explain the contribution of the United Nations to the maintenance of international peace and security? “More than ever in the history of humanity, we share a common destiny. We can only master it if we face it together. And that's why we have the United Nations. (Annan: 2001) It is generally considered that international organizations should be responsible for preserving global stability and peace, whether social, financial or diplomatic; they must also act in the interests of international society. The UN was established for the principle of defending and maintaining international peace and security, which combines many responsibilities to reshape the world in a new reasonable way. Tim Dunne describes the United Nations as “a multi-purpose agency oriented towards specific objectives, including collective security, peacekeeping, health, environment and human rights” (Dunne, 2007, p. 103 ). To the extent that the UN is a “multi-purpose” organization, it would be inappropriate to explain its contribution to the international arena focused on a specific objective; therefore, this article will present a description of the UN and its activities, followed by an empirical assessment of realism in UN peacekeeping. The final section will present a perspective of IR theory that is relevant to the role of the UN in maintaining peace and security. UN peace and security activities have achieved unquestionable quality as tools of international activity because of their promise of forming a highly impartial force. world. After its establishment in 1945, the UN adopted the idea of ​​collective security, played an important role in decolonization, and launched a series of activities such as peacekeeping, peacemaking, establishment of peace. conflict resolution model. The final method with which IR describes the United Nations' contribution to peace is the perception of humanitarian intervention. Collectively with the Responsibility to Protect proposition, the perception of humanitarian intervention is one segment of a broader set of conflict management principles and tools that have helped improve the world. These patterns have caused the decline of mass atrocities, wars, genocides and armed conflicts (Western, 2011). As this article has established, the topic "How IR explains the UN's contribution to peace and security" elicits a range of views and understandings subject to the school of thought that the we continue. IR theory is an important area in understanding international issues specifically reducing the prospects of war; Significantly, this theory has become a fundamental facet of the United Nations system..