Optimal scheduling of transmission delay and heat storage of heating network can significantly improve the flexibility of the electricity-heat integrated energy system, while achieving economic operation of the system, further improving the new energy consumption of system. Therefore, day-ahead optimal scheduling strategy of electricity-heat integrated energy system is proposed considering transmission delay and heat storage of heating network. Firstly, a heat storage system model describing the transmission delay and heat storage of the heating network is established. Then, combining with the specific energy equipment model, the heating network is used as a scheduling resource to participate in the day-ahead optimal scheduling, and a day-ahead optimal scheduling model considering the transmission delay and heat storage of heating network is proposed to realize the scheduling and utilization of the virtual energy storage in the heating network. Finally, a typical example is given to verify the effectiveness of the proposed method. The simulation results show that the proposed method can further reduce the operating cost of the system and improve the consumption rate of wind power by using the transmission delay and heat storage of heating network.