Abstract: By analyzing some general energy consumption model from the EnergyEfficency(EE) perspective, an EE model was presented for applying to Cloud-Computing data centre’s actual scenario. By analyzing the mathematical formula of the EE model, a corresponding strategy of EE optimization was presented and verified on the CloudSim Platform. The experimental results showed that the strategy based on the classic genetic algorithm can significantly improve the integral EE value of server cluster. Furthermore, the robustness of our strategy was also validated by modifying the relevant parameters of the experiment.