二七五八
回顧聯合國憲章的原則，考慮到，恢復中華人民共和國的合法權利對於維護聯合國憲章和聯合國組織根據憲章所必須從事的事業都是必不可少的，承認中華人民共和國政府的代表是中國在聯合國組織的唯一合法代表，中華人民共和國是安全理事會5個常任理事會之一，

決定：恢復中華人民共和國的一切權利，承認她的政府的代表為中國在聯合國組織的唯一合法代表並立即把蔣介石的代表從它在聯合國組織及其所屬一切機構中所非法占據的席位上驅逐出去。

就聯合國方面解讀，此案並非聯合國驅逐代表，而是外交承認問題。
即中華人民共和國取代中華民國常任理事席位，且中華民國不復存在。
故在聯合國方面官方說法上，從未出現開除會籍的情形。

United Nations General Assembly Resolution 2758

United Nations General Assembly Resolution 2758, adopted on October 25, 1971, replaced the Nationalist Republic of China (ROC) with the Communist People's Republic of China (PRC) as the sole representative of China in the United Nations.

Controversy
The Resolution has been criticized as illegal by the Republic of China government, since expulsion of a member requires the recommendation of the Security Council and can only occur if a nation "has persistently violated the Principles contained in the present Charter," according Article 6. According to the Government Information Office of the Republic of China (Taiwan):
So flawed is this Resolution that only its effective repeal by the General Assembly can provide any hope of expunging the stain on the U.N.’s escutcheon in the international system. Taiwan partially adopted this strategy, and attempted to begin a debate on the repeal of Resolution 2758 during the Fifty-Second General Assembly. Although turned aside in 1997 by the P.R.C.’s energetic diplomatic lobbying, the issue of the R.O.C.’s status at the U.N. will not disappear.
A resolution calling for review of Resolution 2758 noted, "As to its return to the United Nations, the Government has made it clear that it no longer claims to represent all of China, but that it seeks representation only for its 21.8 million people".
However, according to the UN website, no member state has ever been expelled from UN since its inception.
Supporters of ROC admission to the UN argue that the resolution only asserts that the PRC is the legitimate government of China, but makes no mention of the ROC being an illegitimate government, nor of which (if either) is the legitimate ruler of the island of Taiwan, Kinmen, Matsu, and the Pescadores.
Opposers of ROC admission to the UN argue that the PRC is the sole legitimate government of China with Taiwan islands as part of it. The representation of Taiwan islands is already included in Chinese representation in the UN. So the application for the representation of Taiwan in the UN raises the problem of the dual representation of the same region, which is against the generally accepted principle of international laws.
From the viewpoint of the PRC, the ROC is no longer the international legitimate representative government of China since the Resolution 2758, and only the PRC represents the whole sovereignty and territory of China, including Taiwan islands.
Supporters of Taiwan admission to the UN argue that the resolution only asserts that the PRC replaces the ROC as the legitimate representative of China, but makes no mention of the sovereignty issues regarding the island of Taiwan and the Pescadores.
Recently, the US reportedly informed the UN Secretary General Ban Ki-Moon that the resolution only solved the issue of China's UN representation, but did not state that Taiwan is part of China. Japan and Canada also endorsed the US position on this issue. [2] This came after the UN Secretary General arbitrarily rejected Taiwanese application to join the UN under the name "Taiwan" base on his interpretation of the UN Resolution 2758 and his observation that majority of the international community views Taiwan as a part of China.

from wikipedia