The planning and construction of integrated energy system is an important part of building a clean, low-carbon, safe and efficient modern energy system. To solve the problem of insufficient flexibility and synergy in the joint planning method of energy station and multi-energy network of integrated energy system, this paper proposes a station-network-load collaborative optimization planning method of integrated energy system in which flexible distribution of load is taken into consideration. Firstly, based on the graph theory and the P-median model, the integrated energy system planning method is proposed, in which the flexible distribution of load is taken into consideration, including the location of energy stations and the network layout considering the interconnection between stations. Secondly, the integrated energy system operation architecture is constructed that takes into account network constraints, and a collaborative configuration model of energy station equipment, load-side equipment and multi-energy network pipeline capacity is further established. Finally, the station-network-load collaborative optimization planning model of the integrated energy system is established, and it is transformed into a mixed integer linear programming problem to solve. Moreover, a system planning scheme including energy station location, network layout and equipment configuration is obtained. The analysis of an example shows that the method proposed in this paper can be adopted to effectively reduce the cost of system investment and construction and the power loss of network transmission, and to make the planning scheme more economical and reasonable. © 2023 Science Press. All rights reserved.