Field measurements have been carried out by using a 427m long pier in high and low wave conditions. Horizontal current velocities and surface elevations were me
asured for twenty minutes every two hours at one or two measurement stations in the surf zone. A series of measurements was continued about two weeks. The breaker properties such as breaker type and breaking position were visually observed several times a day. The bottom profiles along the pier were also measured once a day.
　The relationships between the cross-shore sediment transport rates and flowparameters are investigated by assuming three independent mechanisms of sand transport and by examining the contribution rates of the mechanisms to the cross-shore sediment transport rates. The time-averaged cross-shore velocity, the orbital velocity, and the forward asymmetry of the velocity, which are strongly related to the cross-shore sediment transport, are investigated with respect to the wave parameters such as the wave height, the wave periods and the wave nonlinearity parameter.