Based on the hydrological conditions of Tongzhou Bay and two dimensional nested gird tidal current and sediment numerical model and the measured data of hydrology and sediment，we simulate and verify the movement of tidal current and the sediment concentration in reclamation of the aqueduct of Tongzhou Bay.The simulation fits well with the measured data.Then，we calculate and analyze the movement of tidal current and sediment by the harbor basin surrounding sea with two engineering projects.The results show that hydrodynamic simulation of flow field can reflect the evolution of the current field and the changes in suspended sediment concentration near the ocean.The flow rate and erosion intensity increase of the reclamation area to the south，that is beneficial to the construction of deepwater wharf.Under the two engineering projects，the flow rate and direction are different.The range and the intensity in erosion and deposition of the second scheme are smaller than the first one.