order to evaluate energy utilization scientifically and reasonably, use energy effectively, and provide scientific management basis for energy saving of the future, an improved grey relational analysis was used to build an energy evaluation model for enterprise or project. Firstly, the energy consumption of various types was identified as the reference sequence, the total energy consumption was identified as the compare sequence. Secondly, the evaluation index was normalized, then we got correlation coefficients, relevancy was obtained by combined the correlation coefficient with the weight of each data in reference sequence which was got by AHP. Finally, the model was checked by an energy evaluation of a real estate residential project. The simulation results are correct and reliable. Thus, the feasibility and effectiveness of the utilization of the improved grey relational analysis in energy evaluation was proved, and the basis for decision making was obtained for energy manager.