Abstract: This paper presents an integrated energy station equipment selection and capacity optimization method based on vertex subgraph decomposition and merging principles. Using an energy hub (EH) modeling approach grounded in graph theory, the method captures multi-energy flow coupling relationships and distribution characteristics within stations. The vertex subgraph decomposition and merging principle abstracts equipment options as vertex subgraphs, transforming equipment selection into a subgraph combination and merging problem. By analyzing the multi-energy flow balance network topology, we establish collection-distribution nodes and an energy flow correlation matrix for equipment options. These options are incorporated into the model's constraints through a combination of 0-1 and integer variables. Considering both economic and energy-saving indicators, we develop a mixed-integer linear programming model encompassing equipment selection, capacity configuration, and operational constraints. Case simulations verify the method's effectiveness in achieving coordinated equipment selection and capacity planning. The proposed approach demonstrates rational and effective solutions for comprehensive energy station design, addressing equipment selection, structural construction, and capacity configuration from initial planning stages.