The purpose of this article is to critically examine the existing discourse on the reunification of the Korean peninsula and the Chinese “one country-two systems” construct and to provide a method of approach to realistically feasible strategies for peace and prosperity. Most of the Korean discourse on the establishment of a peace system on the Korean peninsula and the reunification of Korea and the case of “one country-two systems” in China favor a gradual, phased approach based on functionalism theory. However, these studies do not recognize the political reality of separate states with independent sovereignty and substantially different 30systems. As a result, conflicts and confrontations continue despite non-political exchange and cooperation between the two Koreas. In order to solve or minimize these problems, I suggest a “two sovereign states-two systems” approach for peace and prosperity on the Korean peninsula and Northeast Asia, with their security guaranteed by the four major powers around the two Koreas.