The United Nations Security Council (UNSC) is one of the six principal organs of the United Nations (UN) and is charged with ensuring international peace and security, recommending the admission of new UN members to the General Assembly, and approving any changes to the UN Charter. Its powers include establishing peacekeeping operations, enacting international sanctions, and authorizing military action. The UNSC is the only UN body with the authority to issue binding resolutions on member states.

Like the UN as a whole, the Security Council was created after World War II to address the failings of the League of Nations in maintaining world peace. It held its first session on 17 January 1946 but was largely paralyzed in the following decades by the Cold War between the United States and the Soviet Union (and their allies). Nevertheless, it authorized military interventions in the Korean War and the Congo Crisis and peacekeeping missions in Cyprus, West New Guinea, and the Sinai Peninsula. With the collapse of the Soviet Union, UN peacekeeping efforts increased dramatically in scale, with the Security Council authorizing major military and peacekeeping missions in Kuwait, Namibia, Cambodia, Bosnia and Herzegovina, Rwanda, Somalia, Sudan, and the Democratic Republic of the Congo.

The Security Council consists of fifteen members, of which five are permanent: China, France, Russia, the United Kingdom, and the United States. These were the great powers that were the victors of World War II (or their successor states). Permanent members can veto (block) any substantive Security Council resolution, including those on the admission of new member states to the United Nations or nominees for the office of Secretary-General. This veto right does not carry over into any General Assembly or emergency special sessions of the General Assembly matters or votes. The other ten members are elected on a regional basis for a term of two years. The body's presidency rotates monthly among its members.

Resolutions of the Security Council are typically enforced by UN peacekeepers, which consist of military forces voluntarily provided by member states and funded independently of the main UN budget. As of November 2021, there have been 12 peacekeeping missions with over 87,000 personnel from 121 countries, with a total budget of approximately $6.3 billion.

China is one of the charter members of the United Nations and is one of five permanent members of its Security Council.

One of the victorious Allies of the Second World War (the Chinese theatre of which was the Second Sino-Japanese War), the Republic of China (ROC) joined the UN upon its founding in 1945. The subsequent resumption of the Chinese Civil War led to the establishment of the People's Republic of China (PRC) in 1949. Nearly all of the Chinese mainland was soon under its control and the ROC retreated to the island of Taiwan. The One-China policy advocated by both governments dismantled the solution of dual representation but, amid the Cold War and Korean War, the United States and its allies opposed the replacement of the ROC at the United Nations until 1971, although they were persuaded to pressure the government of the ROC to accept international recognition of Mongolia's independence in 1961. The United Kingdom, France, and other allies of the United States individually shifted their recognitions of China to the PRC and Albania brought annual votes to replace the ROC with the PRC, but these were defeated since—after General Assembly Resolution 1668—a change in recognition required a two-thirds vote.

Amid the Sino-Soviet split and Vietnam War, United States President Richard Nixon entered into negotiations with Chinese Communist Party Chairman Mao Zedong, initially through a secret 1971 trip undertaken by Henry Kissinger to visit Zhou Enlai. On 25 October 1971, Albania's motion to recognize the People's Republic of China as the sole legal China was passed as General Assembly Resolution 2758. It was supported by most of the communist states (including the Soviet Union) and non-aligned countries (such as India), but also by some NATO countries such as the United Kingdom and France. After the PRC was seated on 15 November 1971, Nixon then personally visited mainland China the next year, beginning the normalization of PRC-US relations. Since that time, the Republic of China has softened its own One-China Policy and sought international recognition. These moves have been opposed and mostly blocked by the People's Republic of China, forcing the Republic of China to join international organizations under other names, including "Chinese Taipei" at the International Olympic Committee.

The Republic of China's most recent request for admission was turned down in 2007, but a number of European governments—led by the United States—protested to the UN's Office of Legal Affairs to force the global body and its secretary-general to stop using the reference "Taiwan is a part of China".