The era of Supergrid is about to happen with electricity produced by wind and solar power in Mongolia. This will connect China, Japan, and Korea allowing them to share green energy. Stakeholders of those countries initiated a study on 2GW Electricity Grid and no technological problems have been found. Future tasks are to build business models along with the government. On the other hand, China is going to introduce the Nationwide Cap-and-Trade system in 2017, while Korea has introduced it since 2015 and Japan at the regional level long before. Will there be any chance for ‘carbon market linkage’ between the countries? Will there be new ‘Rapprochement’ in pursuit of those green cooperation in the East Asia