This study was carried out in the urban area of Tonglu County. The SWMM-MIKE11 coupled model was established to assess the drainage capacity of the existing pipeline system, and the urban waterlogging in the cases of the storms that occurred every five years, ten years, and twenty years, respectively, was predicted. On this basis, waterlogging risk charts were drawn. The results show that there is a fairly high risk of waterlogging in Tonglu County, and the SWMM-MIKE11 coupled model has strong applicability in Tonglu County and can be used in urban waterlogging risk assessment.