A systematic study of waves,nearshore currents and sediment transport related to the coastal evolution of sand beach under the action of wave,has been carried out.On the basis of the resalts,a numerical model of sand beach evolution around coastal structures has been established.To predict the bed topography,the sediment transport rates of bedload and suspended load under the action of wave and nearshore current as well as the effects of wave on the sediment are wnsidered.The sand beach evolutions caused by a breakwater and a settled ship near the shore are simulated.