As the global price of oil is rising recently, the interest in energy security has increased internationally. In particular, Northeast Asia is more interested in energy security than are other regions, because Northeast Asian countries are predicted to achieve high economic growth over the next decades. In the background, China, South Korea, and Japan with poor natural resources, are competing with each other for the energy resources in Russia's eastern region, which is adjacent to Northeast Asian countries. Russian has the intent to strategically use its energy resources for the buildup of influence over Northeast Asia. The purpose of this article is to find cooperative solutions for energy security in Northeast Asia. First of all, we analyze the present situation of Russia's energy resources. Then, we describe the present conditions of energy cooperation in Northeast Asia and the associated challenges. Based on this analysis, we suggest cooperative ways to enhance energy security in Northeast Asia. Northeast Asian countries need to seek multilateral, cooperative solutions for energy security even though they have been in competition with each other, focusing mainly on bilateral cooperation with Russia. Energy cooperation in the gas sector, rather than the oil sector, is expected to be more reliable due to the R/P ratio and the great cost of development. Joint participation of NEA countries in energy resource exploration, construction of energy transportation infrastructure and processing facilities in the eastern regions of Russia, use of “asset swap” mechanism, rather than the conventional “resource extraction” approach, will make great contribution to enhancing energy security in NEA.