The sudden siltation is one of the key issues in the construction of Lianyungang waterway.A 3D numerical model which contains modules of wind,wave,tide and sediment is established to simulate and study the wind wave,tide and sediment during Typhoon Wipha in Lianyungang sea area.The results are in high coincidence with the observed data.The variation of water level and the characteristics of spatial distribution of tide and sediment in the said waters during Typhoon Wipha are also analyzed herein.The model is then used to predict the siltation during the construction of Phase II Lianyungang waterway project in typhoon period.The result shows that the navigation obstruction due to sudden siltation would not occur in Lianyungang waterway under the impact of a strong wind like Typhoon Wipha.