The main influencing factors of suspended sediment concentration are hydrodynamic conditions.Studying the impact of hydrodynamic forces on aquatic plants in Taihu Lake is conducive to improve the water ecology of Taihu Lake by improving hydrodynamic conditions.We apply 3D water dynamic and ecological numerical simulation software to setup lake current model and wave model of Taihu Lake，verify the model results，and use verified current and wave model results as input parameters of suspended sediment model to calculate the change of scouring and silting and the concentration of suspended matter in Taihu Lake at different current and wave conditions.The results show that driving force of hydrodynamic is wind，the larger wind speed causes the larger current speed and wave height in the lake，and the concentration of suspended sediment caused by current and wave becomes larger.The mathematical model can well simulate the relationship among current，wave and suspended sediment concentration of Taihu Lake.