Abstract: Express highway service area is a place to provide rest, refuel, maintenance and repair services for the drivers, and has higher requirement for flood control and drainage. In order to quickly find out and solve the waterlogging problems in the service area, firstly, the traditional SWMM model of single drainage system was used to simulate the rainstorm in a service area with rainfall recurrence periods of 2, 5, 20 years, the underground pipe network drainage conditions were analyzed. Secondly, based on the traditional model, the dual-drainage system theory was used to improve the model, and the surface waterlogging conditions were analyzed. Finally, the drainage system was optimized by using low impact development (LID) measures and pipe diameter modification in view of waterlogging conditions. The simulation results show that there are some pipelines overloading and no waterlogging for a recurrence period of 5 years; for a recurrence period of 20 years, most area are waterlogged and the maximum waterlogging depth is 30 cm; after taking optimization measures, the drainage problem can be basically solved in the service area. The results can provide a technical reference for analyzing and solving waterlogging problems.