Abstract: To conduct the urban flood risk simulation in areas without drainage pipe survey data, taking the catchment area in Yuelai New Town, Yubei District, Chongqing City as the study area, four equivalent methods were adopted to represent the drainage capacity, that is discounted rainfall method (DRM), the equivalent infiltration approach in all areas (EIA), equivalent infiltration approach on road only (EIR), and the stormwater manhole equivalent infiltration method (SME).And an urban flood model based on the Finite Volume Coastal Ocean Model (FVCOM) was established.An idealized case and the measured rainfall data were used to validate the flood model.The equivalent method with the best performance was used to simulate and analyze the flood characteristics under different rainfall types in the study area, and the flood risk was analyzed based on the flood hazard index.Results show that the average relative errors of the flood areas simulated by DRM, EIA, EIR, and SME are 36.49%, 43.31%, 8.18%, and 4.42%, respectively, and the performance of SME was the best, but there may be limitations in areas without street views.Under the same rainfall return period, the flood accumulates faster at the initial stage of rainfalls that have earlier peaks, while the flood risk caused by rainfalls with later peaks is relatively higher.In case of the same rainfall peak, the larger the return period, the greater the flooding area and volume, and the higher the overall flooding risk.The proposed method can technically support urban flood management, especially for areas where drainage pipe data is unavailable.