Northeast Asian countries have no multilateral security and cooperation regime such as OSCE in Europe and ARF in Southeast Asia. Over the last decade, Korea, Japan, and Chinese cooperation aimed at economic integration has gradually increased in this region. However, antagonism and distrust, which resulted from territorial conflicts, historical animosity, and North Korea’s provocations, have prevented them from building a security regime or organization. The European countries founded OSCE through the Helsinki Accord in 1975. ASEAN also held the first ARF for official consultations on peace and security issues in 1994. After North Korea’s missile launch and nuclear test, China initiated the Six-Way Talks to resolve the nuclear-missile program of the North, and to relieve the tension in Northeast Asia in 2003. The Six-Way Talks was expected to turn its role into a security regime after successfully resolving the issue. But, they seem to have come to nothing since North Korea refuse give up their nuclear-missile program. On the other way, as an irreversible trend, scholars and experts emphasize the evolution of institutional arrangements for a regime for multilateralism in Northeast Asia. Those suggestions and obstacles to building a security and cooperation organization will be examined in this article. Also, the leadership of the Trilateral Cooperation Secretariat is expected as an important role for a mini-multilateralism in Northeast Asia.