Abstract: In order to objectively evaluate the implementation value and effect of power energy efficiency project, a systematic comprehensive evaluation model is presented in this paper. Current researches can only evaluate the project involving one single participant or mainly are lateral assessment, which lack integrity. So a comprehensive evaluation index system with multi-level and multi-dimension characteristics is built through in-depth analysis of the project cost benefits of all relevant participants. The system contains four aspects, which are grid operation, environmental benefits, economic efficiency and resource utilization. In addition, a comprehensive evaluation method that combines AHP and TOPSIS is put forward to overcome the shortcoming that AHP over depends on the decision maker's subjective experience. In the end, by taking Zhangjiakou system as example, the rationality and feasibility of the model are verified. The proposed comprehensive evaluation method can provide scientific evaluation for energy efficiency projects and beneficial theoretical reference for decision-maker.