China’s burgeoning economic growth has been accompanied by soaring demand for electricity. Conscious of worsening pollution in Chinese cities due to increased coal-fired electricity generation, and of growing global concerns about greenhouse gas emissions, Chinese authorities are planning to continue massive investments in hydropower generation. This study uses Sino TERM, a dynamic multi-regional model of the Chinese economy from the TERM family, to examine investment scenarios across China. Preliminary results indicate that (1) Hydropower can significantly boost local economic development, driving a GDP growth of 43% per year on average. It can promote the development of some industries such as construction, trade, transport, and machine equipment, but have a little impact on overall national economy. (2) Hydropower can provide 300 billion kW·h of power annually, thus alleviating conflicts between the supply and demand and ensuring China’s energy security. (3) Hydropower can replace 96 million tons of standard coals each year, reducing 200 million tons of CO2 emissions, 2.59 million tons of SO2, with prominent effects on energy saving and emission reduction. Hydropower proportion increases by 1.6%, which is conducive to improving the electric power consumption structure.