In order to give full play to the utility of electric/thermal flexible loads in the integrated energy system of the park, this paper firstly establishes an electric flexible load model based on the translatable, transferable and curtailable loads, and at the same time establishes a thermal flexible load model based on the ambiguity of the users' perception of the temperature; subsequently, a mixed-integer linear programming method is used to optimize the configuration of the integrated energy system of the park, with the objective function of minimizing the sum of the system's carbon trading cost, operation and maintenance cost, compensation cost, electricity purchase cost, gas purchase cost, wind and light abandonment penalty cost and investment cost. The minimum of the sum of carbon trading cost, operation and maintenance cost, compensation cost, power purchase cost, gas purchase cost, wind and light abandonment penalty cost and investment cost is taken as the objective function to optimize the configuration of the integrated energy system in the park, and obtain the optimal capacity of each device and the output of each time period. The results show that by scheduling flexible electric loads, the electric and thermal load curves can be optimized and the consumption of renewable energy can be promoted, so as to increase the installed capacity of the wind turbine, reduce the capacity of the gas turbine, the storage battery and the heat storage tank, and improve the economy of the system.