Abstract: Based on internal production and supply mechanism of power system and the NSBM model,this paper opens the “black box” of the system and investigates the environment technical efficiency of total electrical industry, power generation and power network from 1995 to 2012 in China, involving the energy and environmental factors in the input-output system. The conclusion is that the environment technical efficiencies of Chinese electrical industry are very low. The reform in 1998 which detached government from enterprises promoted the efficiency, while the other reform in 2002 which detached power from grid did not. A U-shaped relationship is found between the proportion of state ownership and the efficiency of power generation, and the threshold value is 69.6%. More and more areas are located in left of the threshold value after 2002. Regional electricity trade promotes the environment technical efficiency of power generation, but does not promote that of power network. The environment technical efficiency in the areas of coal resources accumulation is low, indicating that these areas probably abuse resources and lack of environmental governance, and the paradoxical “resource curse” and “pollution heaven” hypothesis existing between areas.