Since the Second World War, the degree of legalization of the international community has enormously increased, to which the United Nations (UN) has made important contributions. As a symbol of morality and legitimacy, the UN can balance the interests of big and small countries properly and utilize its advantage of networking institutions to further the rule of law in conflict areas and the field of development. The UN would not have been able to make such achievements without the support of its member states, especially the support of major powers. With the restoration of China’s lawful seat in the UN as well as the gradual growth of power and change of ideas, China has made significant contributions to the international rule of law under the UN framework. Chinese contributions include the formulation of the UN Charter, safeguarding and responding to the UN’s international rule of law, and the creative development of UN Charter’s values and ideas, such as the Five Principles of Peaceful Coexistence, the “One Country, Two Systems” and a Community with a Shared Future for Mankind. As anti-globalization and populism are rising and uncertainties are growing in international society, it is imperative to strengthen the international rule of law within the framework of the UN.