Abstract: Energy efficiency is the recent focus of every country. In this paper, based on the model of endogenous growth, equilibrium solution and the optimal theory of energy efficiency were calculated; and the dynamic comparative analysis was carried out on the balanced solution, optimal solution and the actual value of China from 2001 to 2008. The development path of energy consumption and energy efficiency from 2010 to 2050 was forecasted. At last, the optimal development model was formulated through simulation under different scenarios of economic growth. The results showed that there was a strong trend of inertia in the dynamic development of China's energy efficiency, and the gap of its actual value and optimal value mainly could be mainly attributed to economic development model. Under the current development model and with the annual 8% economic growth rate, the peak of energy consumption would be reached at 2040, while under the optimal development model, the peak would be reached at 2036, but energy consumption of the former would be 2.71 times as the latter. Therefore, to pursue the sustainable development, the right development model must be estabilished, and following that, efficient political, economic, cultural and social systems need to be built.