The East China Sea is a productive sea. Its annual total fishery production including the Yellow Sea is about 9.2 million tons, about 10% of the world′s total fishery production. For a sustainable development and wise use of natural resources in the East China Sea, cooperative international programs on marine ecosystem research among surrounding countries, China, Korea, Taiwan and Japan, are necessary. In this review paper, published papers and reports on the East China Sea are summarized and possible collaborative researches with the surrounding countries, especially with China, are sought.