This paper focuses on the optimal scheduling of the district energy system with multiple energy supply modes and flexible loads. For multi-energy system (MES), the energy hub (EH) model including energy storage system and integrated electric vehicle (EV) is established. Based on the model, the influence of pollutant trading market on total operation cost is analyzed, and the optimal scheduling strategy is further put forward to realize the minimum purchase cost and emission tax cost of the MES. Finally, this paper compares the economic benefit of the fixed mode and the response mode, and discusses the contribution of the energy storage device and the multi-energy complementary mode to energy utilization efficiency. The simulation results indicate that optimal scheduling strategy of the EH can coordinate various energy complementary modes reasonably. Meanwhile, the proposed strategy is able to improve the operation economy of the EH, and ensure the better response effect of the demand side. The sensitivity analysis demonstrates the impact of pollutant emission price change on emission reduction.