Northeast Asia is the most developed region in Asia with large energy demand,and plays an important role in the global economic development.Northeast Asia has been facing severe challenges in ensuring energy security,protecting the environment,and coping with climate change,because of their high dependency on fossil fuels and imports of oil from outside the region,and inverse distribution between energy resources and demand.As an important part of Asian Energy Interconnection,the Northeast Asian Energy Interconnection is the core content and plays an important role in promoting the cooperation in Northeast Asia.It would strengthen the interconnection of the energy and power in the region,optimally allocate the energy resources and efficiently use the clean energy,deliver the sustainable development of the economy,society and environment in Northeast Asia,and promote the overall development ofAsian Energy Interconnection.This study is one of Asian Energy Interconnection research series.The content is divided into 6 chapters: In Chapter 1,the development status of the economy,society,energy and power in Northeast Asia is introduced,advantages and challenges of sustainable development and energy transition are analyzed,and development ideas ofNortheast Asian Energy Interconnection are proposed.In Chapter 2,in order to achieve the temperature control target of Paris Agreement,the development trend of energy and power transition in Northeast Asia is prospected,with corresponding proposed scenarios.In Chapter 3,the distribution of clean energy resources and layout of large power generation bases are studied.In Chapter 4,based on the analysis of the power balance,the overall pattern and interconnection schemes of Northeast Asian power grid interconnection are proposed.In Chapter 5,comprehensive benefits from Northeast Asian Energy Interconnection are evaluated.In Chapter 6,policy and mechanism are proposed to related stakeholders.