The reasons why our energy efficiency has changed and its development trends were analyzed by using measurement analysis. Some recommendations are also proposed. Firstly, the energy efficiency and its fluctuations in industrialized countries were discussed. Secondly, based on summing up domestic research status quo, the change reasons of China's energy efficiency were analyzed through logarithmic mean Divisia index. It is thought that that industrial structure is the main reasons why China's energy efficiency has fallen after 2000. Then, using the error correction model technical analyzes of the change trend of energy efficiency under the conditions of increasingly heavy industrial structure in China, and it is concluded that with the formation and development of heavy industrial, China's energy efficiency will continue to reduce. Finally, from changing the economic structure, improving energy price system, speeding up the development of modern service industry. The ways to lower energy consumption, and improve energy efficiency are given. 