Abstract: The aim of this paper is to enhance the operation efficiency of the integrated energy system, increase the absorption rate of new energy and promote the multi-energy flow coupling tightness of the integrated energy system. To achieve these objectives, we construct a day-ahead optimal scheduling model for the integrated energy system with the characteristics of gas-thermal virtual energy storage taken into account. Firstly, a virtual energy storage model of heat network and gas network is established. The heat supply pipeline model is constructed using the flow segmentation method, while the gas network pipeline model is constructed by incorporating the pressure penalty constraint of pipeline. Secondly, a second-order cone relaxation method is employed to linearize the gas network pipeline model. Finally, the day-ahead optimal scheduling scenarios of four types of integrated energy systems are solved through a YALMIP+CPLEX solver called by MATLAB simulation software. Results of numerical examples indicate that the proposed model can enhance the coupling degree among various energies, improve the flexibility of the system, optimize the system operation economy effectively and boost the absorption rate of new energy.