Abstract: The traditional method completely relies on two-dimensional design wiring drawings in the laying construction of railway substation. In order to solve the problems such as twisting, crossing and waste of materials, which are easy to occur when the traditional method is used in the laying construction of railway substation and distribution, the cable laying of railway substation and distribution was optimized based on BIM (Building Information Modeling) technology. Using the improved rapid exploring random tree (RRT^*, Rapid Exploring Random Tree^*) algorithm, the intelligent wiring was carried out in three-dimensional view, which solved the problems of complex cable layout planning, high process requirements, difficult to master the construction process, avoided the occurrence of twisting in the construction process, and implemented the optimization of wiring path. In addition, the whole cable laying process could be simulated and demonstrated in the form of three-dimensional animation, and a cable list including route, length, specification and model could be generated, which significantly improved the construction efficiency and process quality.