Abstract: Coupled land surface hydrology is helpful to understand the land hydrological processes and their feedbacks at regional scale, investigate the response of water disasters to climate change. In this paper, a coupled land surface hydrology model is applied for the hydrological simulation over the Huaihe River Basin, with the model being evaluated firstly using the station observation, and a 56-year long term simulation is then conducted for extreme hydrological event analysis. According to the time series of simulated and observed streamflow at Bengbu Station of the Huaihe River Basin, Pearson-Ⅲ distribution method is used to calculate the designed streamflow values at Bengbu corresponding to five different return periods. The results show that reasonable designed streamflow can be obtained with both the simulated and observed streamflow time series, but for the extremely high values, the fitting accuracy by using observed streamflow is better than the result based on the simulated streamflow series.