Today, terrorism becomes a threat in the form of megaterrorism triggering a transnational disaster that causes reckless and large damage. The Korean government dispatches troops as peace keeping force for various activities in the international society. For this reason, Korea comes to be a target of an international terrorist group. In particular, externally, since South Korea has a hostile relationship with North Korea which is equipped with an advanced ability of terrorism, it always faces the threat of terrorism. Therefore, it is more important to make preemptive prevention and responses in the comprehensive security dimension. In addition, internally, the country has frequence access of foreigners and an increased number of North Korean refugees due to its growing activities in the world; severe social discontent along with the increase in unemployment rate and the widening gap between the rich and the poor; such a structural setting as high population density suitable for new terrorism. In this circumstance, blended terrorism is likely to occur simultaneously. If these external or internal factors trigger complex megaterrorism in an urban area where important national facilities, multi-purpose facilities, or other social infrastructure are concentrated, and thereby a lot of human lives and assets are damaged, it is impossible to respond to such a disaster with limited police force. For this reason, it is inevitable to protect the security of the nation and the public and maintain public order with the use of military force. According to the counter-terrorism system of South Korea, in principle, military force is put in only if a terror is posed to military facilities. In this case, there is no controversy, because the system is well established under the leadership of the Ministry of National Defense and the Joint Chiefs of Staff. If the head of the countermeasure headquarters makes a request of support, exceptionally, it is possible to operate military force as well as military facilities. Even if the exceptional necessity to make up for insufficient police force is accepted, it is unavoidable to restrict military intervention in the private sector strictly in terms of constitutional order. Therefore, this study tries to suggest the establishment of new provisions pertinent to military presence and withdrawal procedures and the scope of work in the Act on Counter-Terrorism when counter-terrorism operation forces exceptionally intervene in a domestic situation, just as in Martial Law Act according to which military forces are allowed to intervene in such a situation as a state of national emergency in order to maintain public order. Essentially, the domestic counter-terrorism activity is use of public power for protecting social order and security. Therefore, in principle, it is required to prevent terrorism and take suppression activity with the use of police force. Exceptionally, if it is inevitable to put in the counter-terrorism operation forces under the Ministry of National Defense, it is necessary to establish new provisions suggested in this study, including ‘the limitations of the counter-terrorism of police force’, ‘the necessity of urgent support’, ‘the proposal by the director of National Counter Terrorism Committee’, ‘the approval by the President’, the control procedures of the National Assembly, such as notification to the National Assembly and the procedure of withdrawal request of the National Assembly, and the scope of work, in the Act on Counter-Terrorism.