《联合国宪章》所确立的集体安全体系与国际联盟的有关规定相比，有着意义深远的进步。然而，随着国际形势的变化，宪章的设想暴露出了这样那样的缺陷，从而使得执行联合国集体安全体系职能面临一系列问题：联合国集体安全体系的政治基础不稳，使得集体安全体系赖以存在的“大国一致”原则难以得到实现；对行使集体强制行动的法律前提缺乏权威性的统一解释；联合国集体强制军事行动所需军队无法建立，联合国维持和平行动缺乏应有的法律规范。对以上几个方面的原因进行分析，有利于国际社会进一步完善联合国集体安全体系，使之对人类的和平与安全发挥更大的作用 The collective security system established by the UN Charter has far-reaching progress in comparison with the relevant provisions of the League of Nations. However, with the changes in the international situation, the tentative plan of the Charter has exposed such deficiencies that the implementation of the UN system of collective security system faces a series of problems: the unstable political foundation of the UN system of collective security and the existence of a system of collective security The principle of “great nation coherence” can hardly be realized; there is no authoritative unified explanation of the legal preconditions for exercising collective coercion; the unworkable military force required by the United Nations for collective coercive military operations can not be established; and the UN peacekeeping operations lack proper legal norms. An analysis of the reasons for the above aspects will help the international community to further perfect the collective security system of the United Nations and play a greater role in the peace and security of mankind