东北亚区域以其地缘优势和经济互补优势，成为21世纪最有发展潜力的经济合作区和世界经济的新增长点。由于各种原因，东北亚区域经济合作一直没有突破性进展。为尽快建立区域经济联合体，必须寻找区域合作的切入点。中日两国直接投资活动是促进该区域经济合作向纵深发展的重要抉择。因此，只有把中日两国直接投资作为东北亚区域经济合作的切入点，才能以点带面，夯实区域经济合作的基础。 With the advantage of its geographical advantages and economic complementarities, the Northeast Asia region has become the new growth point for the most promising economic cooperation zone and the world economy in the 21st century. For various reasons, there have been no breakthroughs in the economic cooperation in Northeast Asia. In order to establish a regional economic association as soon as possible, we must find a starting point for regional cooperation. The direct investment activities of China and Japan are important choices in promoting the deepening of economic cooperation in the region. Therefore, only by taking the direct investment of China and Japan as the starting point for the economic cooperation in Northeast Asia can we lay a solid foundation for regional economic cooperation with a straight line.