Today, the positive participation in Peace-Keeping Operations(PKO) which gain UN's approval and early dispatch of troops to secure international peace and security are regarded as a U.N member's basic obligations and essential elements for a responsible member state to join the family of nations. Therefore the Republic of Korea(ROK) should take part in the UN or multinational PKO in proportion to its national strength. In order for the ROK government to send the Korean armed forces abroad, a National Assembly's approval is needed. But there have been several occasions that we couldn't dispatch troops for UN PKO in proper time because of the delayed National Assembly's consent. From now on, the National Assembly approval should not be an obstacle in the realization of guiding principle of international peace and cooperation that the ROK's Constitution declares. In this context, we should need to simplify the parliamentary approval procedure to make it work as soon as possible.