Abstract: It is easy to form large-scale sedimentation under the tide gate,which may have a serious impact on the operation of the project.As a new type of gate,the double-layer tide gate has been applied to many projects in Zhejiang Province,but its scouring and silting effect has not been systematically studied. Combined with the tidal gate project at the outlet of a large pump station,a 1∶25 physical model is established,and the hydraulic scouring and silting characteristics of different gates are studied with the scouring and silting effect and scouring and silting efficiency as indicators. The research shows that the hydraulic scouring and silting can be solved by running a pump station unit（20 m~3/s）and opening the upper gate within the range of 1～2 m. The effective scouring and silting time under the gate under different working conditions is short,and gully stability time is generally less than 15 min. The lower the water level under the gate,the more favorable it is for sand flushing. Open the one-hole gate for operation,and the scouring and silting flow is relatively concentrated. The apron under the gate can be flushed out within 10 min. If the two-hole gate is opened for operation,the discharge per unit width of the gate can be reduced,which can effectively scour and silt in the initial stage,with high efficiency,but the apron cannot be flushed out completely,and the scouring and silting effect cannot be fully met. When the sedimentation under the sluice is high and the sediment is abundant,the flushing efficiency is relatively high. The double-layer tide gate has good scouring and silting efficiency and effect. The relevant results can be used as a reference for design and operation management