District Integrated Energy System (DIES) are characterized by multiple levels and multiple operators. This makes it difficult to optimize scheduling using traditional centralized methods. In this paper, an optimal dispatch method of DIES considering ladder-type carbon trading mechanism and demand response is proposed. This approach protects the interests and privacy of different stakeholders, smooths load fluctuations, and controls carbon emissions. Firstly, the structural characteristics of multi-energy stations are analyzed, and a demand response model is constructed on the user side of energy stations. Secondly, a two-level optimal scheduling model is constructed. A step carbon trading mechanism is added to the objective function to reduce the total carbon emissions of the system. Finally, we decouple and solve the inter-level optimization sub-problem by using the analysis target cascade (ATC). The simulation results show that the proposed scheduling method can give consideration to the interests of all subjects. It can improve the low carbon of system operation and meet the actual scheduling requirements.