With the development of the energy internet, the types and forms of energy utilization are becoming increasingly diverse. In this paper, the concept of multi-energy system is redefined. Based on this, the multi-input and multi-output model of the system is established. At the same time, a general evaluation system suitable for multi-energy is also given. The energy utilization level of the system is evaluated by the energy efficiency and the global energy consumption ratio. Finally, taking the energy utilization of a college campus as an example, the energy allocation of the system is optimized to obtain the optimal energy ratio. It aims to provide advice for the planning and design of energy transportation and provide a reference for mitigating the energy crisis.