Abstract: Under the background of "carbon peaking" and "carbon neutrality", a low-carbon economic operation strategy of integrated energy system (IES) based on the stepped carbon trading mechanism and refined electricity-to-gas and carbon cycle is proposed in order to improve the low-carbon utilization of energy. Firstly, stepped carbon trading mechanism was considered, the interval number and carbon trading cost were used to control carbon emissions. Secondly, on the basis of refining electricity-to-gas, electrolytic cells and methane reactors was introduced, and carbon capture devices was added to achieve carbon recycling. Finally, an IES optimal dispatching model was constructed with the goal of minimizing the total cost, including energy purchase costs, stepped carbon emission trading costs, wind and light curtailment costs, and carbon capture costs. The CPLEX modeling optimization engine was used to transform the original problem into a mixed integer linear problem and solve it. The results verified the effectiveness of the proposed model.