The concept of national security and the fundamental system for crisis management have departed from traditional methods and the importance of a national critical infrastructure crisis management has been emphasized. A national critical infrastructure crisis means a situation where human resource, material and functional system that may have a material effect on the critical functions of the government, the vitality and integrity of society, national economy and the safety of the public becomes disabled due to causes such as terrorism or major disasters. Although North Korea had been subject to numerous rounds of negotiations and sanctions as it continually developed nuclear weapons since the 1960s, it has also showed off its nuclear armaments through successful nuclear testings and missile launches. As the development and threat of North Korea's weapons of mass destruction becomes more noticeable and the range of its risk expands, this study focuses on the potential for an absence of leadership for national crisis management where the country's leadership, which should serve the critical role and function of handling national crises, becomes completely destroyed by the unexpected initial attacks by North Korea. As a result, the purpose of this study is to propose safety measures for the country's leadership in preparation for North Korea's threat of nuclear weapons by examining the concept and degree of risk of weapons of mass destruction with a focus on nuclear weapons, analyzing the substance of the threat of North Korean nuclear weapons and evaluating such threat. In conclusion, first, to ensure the normal functioning of a national crisis management system in the event of a national crisis, we must seek safety measures that conform to the scope and succession order of the leadership of the national crisis management for an Enduring Constitutional Government (ECG) and the Continuity Of Operations (COOP). Second, in the event of a national ceremony, the gathering of the country's leadership all together in an open place should be avoided. In unavoidable circumstances, the next in rank that will act on behalf of the current leader should be designated and relevant safety measures should be taken. Third, during time of peace, in preparation for national crises, the scope of protection for the country's leadership should be prescribed and specific security and safety measures should be implemented. Fourth, the succession order for acting president in the case of the death of the president pursuant to Articles 71 and 26(1) of the National Government Organization Act should reconsidered to see whether it is a reasonable provision that takes into consideration a national crisis management that corresponds to the threat of North Korean nuclear weapons and weapons of mass destruction. Pursuant to the Basic Guidelines for National Crisis Management set out under Presidential Directive No. 229, the Korean government is currently operating a case-by-case "crisis management standard manual" and its sub-manuals and has also prepared the Presidential Security Service's security and safety measure regulations regarding the acting president. Therefore, the Korean government should actualize the above points in the case-by-case crisis management standard manual and security and safety measure regulations regarding the acting president to implement and legislate them.