According to the UN Charter (Article 26), the UN Security Council is the primary organ responsible for the maintenance of international peace and security. Nuclear states agreed to the adoption of a UN Security Council Resolution that provided positive security assurances. The adoption of UN Security Council Resolution №255 on June 19, 1968, was of particular significance. This resolution stipulated that instances of aggression involving the use of nuclear weapons or the threat of such aggression against a non-nuclear-weapon state would require immediate action by the UN Security Council and its permanent members, who are nuclear-armed states. The aim of the work is to determine the role of the UN Security Council in the system of preventing the proliferation of nuclear weapons. The methodological basis of the study will focus on the analysis and understanding of the impact of the UN Security Council on strategies and measures aimed at preventing the spread of nuclear weapons in the international context. The results of our research have shown that the role of the UN Security Council in the disarmament of Iraq’s nuclear program, which could have led to the development of nuclear weapons, proved to be significant. To achieve this, in accordance with UN Security Council Resolution №687 adopted on April 3, 1991, the Special Commission (UNSCOM) was established. During an extraordinary meeting of the UN Security Council at the highest level on September 24, 2009, Resolution UN Security Council Resolution № 1887 was adopted, aimed at supporting nuclear non-proliferation, criticizing Iran and North Korea. Resolution №1887 outlines measures to strengthen control and the rights of nuclear-weapon states to demand the return of nuclear materials and equipment in case of violations of the Non-Proliferation Treaty or withdrawal from it. It also involves enhancing security measures for the storage of nuclear materials and strict export controls. Conclusions. In our opinion, the powers of the UN Security Council in the field of non-proliferation of weapons of mass destruction should be utilized more promptly and effectively. The insufficient effectiveness of this international mechanism in preventing proliferation remains a cause for serious concern among UN members worldwide. To enhance the effectiveness of the UN Security Council, we propose the adoption of a comprehensive resolution that includes provisions on the procedure for a state’s withdrawal from the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and its violation of commitments to refrain from acquiring nuclear weapons. This resolution should stipulate the imposition of sanctions against such a state based on a special report from the International Atomic Energy Agency (IAEA). Such a mechanism can ensure an effective impact of the international community on states that withdraw from the NPT.