This article analyzes and evaluates “the third nuclear weapons test by North Korea from the Internationallegal points of view.”The North Korea conducted a third underground nuclear test at a site in the northeast of thecountry(February 12, 2013), claiming that a 'miniaturized and lighter' atomic bomb was used in the 'successful'detonation. Pyongyang’s third nuclear test poses a completely different level of security from two previous onesin 2006 and 2009. The Washington-based Nuclear Threat Initiative (NTI) on its web site counted the reclusivecountry as one of the nine nations possessing nuclear weapons. This might mean that North Korea become ade-facto nuclear weapons state. The UN Security Council has adopted a resolution (No.2094) that strengthensanctions against North Korea for its nuclear and ballistic tests. The resolution targets the illicit activities ofNorth Korean diplomats. the country's banking relations, illegal transfers of bulk cash and add new travelrestrictions. So, this article has six parts.: 1) issue fighting, 2)analysis of third nuclear weapons test by North Korea, 3)international legal norms on nuclear weapons test, 4) advisory opinions of ICJ on nuclear weapons test fromInternational legal points of view. 5) advisory opinions of ICJ regarding the legality of threat or use of nuclearweapons from International legal points of view and 6) conclusion. The International legal points of view above have two aspects: 1) Legality of nuclear weapons test by itself ;2) Legality of the threat or use of nuclear weapons. The former reviews international agreements such as theJoint Declaration on the Denuclearization of the Korean Peninsula, Treaty Banning Nuclear Weapon Test in theAtmosphere, Outer Space and Under Water, Comprehensive Test Ban Treaty(CTBT), Treaty on theNon-Proliferation of Nuclear Weapons(NPT) and UN Security Council sanctions. The latter reviews Interim measures of protection by ICJ to ban Nuclear Test of French (1974) and advisoryopinions of ICJ regarding legality of the threat or use of nuclear weapons(1996). The court must first considerwhether it has the jurisdiction to give a reply to the request of the Generally Assembly for an advisoryopinion. The question put to the ICJ has a relevance to many aspects of the activities and concerns of theGeneral Assembly including those relating to the threat or use of force in international relations, thedisarmament process, and the progressive development of international law. The question put to the ICJ by theGeneral Assembly is indeed a legal one, since the Court is asked to rule on the compatibility of the threat oruse of nuclear weapons with the relevant principles and rules of international law. To do this, the court mustidentify the existing principles and rules, interpret them and apply them to the threat or use of nuclear weapons, thus offering a reply to the question posed based on law. The proportionality principle in international humanitarian law may thus not in itself exclude the use ofnuclear weapons in self-defense in all circumstances. But at the same time, a use of force that is proportionateunder the law of self-defense, must, in order to be lawful, also meet the requirements of the law applicable inarmed conflict which compromise in particular the principles and rules of humanitarian law. Accordingly, in view of the present state of international law viewed as a whole, as examined by ICJ, andof the elements of fact at its disposal, the Court is led to observe that it cannot reach a definitive conclusionas to the legality of the use of nuclear weapons by a state in an extreme circumstance of self-defence, inwhich its very survival would be at stake. However, state practices in international community has changed drastically since advisory opinions of ICJabove(1996) regarding legality of threat or use of nuclear weapons from international legal point od views.. Nuclear Weapons are the most destructive man-made force on the planet. Numerous treaties exist limiting theiruse, and customary international law prohibits such weapons. All states have a legal obligation to forgoproliferation and disarm their current nuclear arsenals. Unfortunately, the enforcement mechanism of the NPT,IAEA and Security Council are ineffective. The Interpretation of the Charter of the UN must change to allow use of force in very limited circumstancesto enforce the legal prohibition against nuclear weapons. Thus, Article 2(4) of the Charter which prohibits useof force that is inconsistent with the purposes of the Charter, and Article 51, which gurantees the right ofself-defense, should be read to allow limited use of force to prevent nuclear proliferation being consistent withthe purpose of the Charter.