A nested tidal current and sediment transport model is established based on ADCIRC+SWAN and Delft3D+SWAN models. All typhoons affecting Tongzhou Bay are classified into 5 types according to the track characteristics，and a typical typhoon for each type is selected to drive the model and calculate the sudden siltation volume of the planned port area in the north of Tongzhou Bay and its surrounding sea areas and analyze the characteristics of seabed morphological evolution. The results show that under the current construction status of the port area，the range of sediment erosion and deposition in Yaosha-Lengjiasha sea area caused by the typhoons are within ± 0.18 m，and the average thickness of erosion and deposition is between 0.05 m and 0.10 m；in the context of considering the impact of the reclamation plan，the channel-sandbank system is not greatly affected by the storm surge，and the magnitude of the storm erosion and deposition is relative small；the deposition amount of all the three different schemes is small after a storm surge，and the maximum local deposition thickness which is mainly controlled by typhoon types is between 0.1 m and 0.6 m. Generally speaking，from the point of view of typhoon sudden siltation，the second scheme of port area reclamation is better. However，the differences among different schemes are small，and it is suggested to consider other factors to achieve the final decision.