From the influential factors of the estuarine and coastal suspended sediment concentration,and based on the field data,the author analyzes the change laws of suspended sediment concentration and establish a three-dimensional high-precision numerical model of suspended sediment concentration change and multi-factor response.On the basis of the measured flow,sediment and wind data of Huangmao waters in Nov.15-19,1992,the author verifies the model.The results show that the model can simulate the flow and sediment movement with stable calculation and high precision.The verified results of flow and sediment movement can basically meet the requirements of precision.