China hydroelectric resource has the world largest theoretical annual energy output which is 6.08 trillion kW·h. China has the world largest theoretical installed capacity which is 6.94 hundred million kW. China has the world largest technical capacity can be developed which is 5.72 hundred million kW. China has the world largest annual output which is 2.61 trillion kW·h. With the rapid development of economic of recent 20 years in China, we built lots of large hydropower projects in the big river which played a large role in the flood control, comprehensive utilization water resource, provision of clean energy and help the sustainable development of economic society. Until the end of 2012, China has the world maximum number of dam been built and under construction. China has the world largest hydropower installed capacity. With the world highest level of different dams design and construction, China is leading the trend of dam design and dam construction. With the construction of many high dams and big reservoirs, the coming 20 year will be the key period of the development and exploit of China water resource. In order to ensure the efficient and safe operation of these hydropower projects, we need to increase the investment and strengthen the research. With the support of science and technology, improved development mode, adjusted development idea, we can resolve the technological problem and other problems that restrict the hydropower development to meet the need of sustainable development of national economy. <<