The sheet-pile quay is an important port structure only used in the small quay construction because of the restriction of the wall height.The large-scale deep water berths will be realized due to that covered sheet pile greatly strengthens the force of the front wall.As a new structure,there is no mature theory and method of covered sheet-pile quay,and the seismic characteristics and mechanism is unclear.The seismic residual deformation and seismic mechanism of sheet pile quay are complex problems in the seismic safe design of sheet pile quays.Based on the nonlinear finite element method,a series of seismic design parameters were considered such as spacing between the covered pile and the wall,seismic acceleration amplitude,the length,thickness,intension of the covered pile.The seismic residual deformation and stress characteristics of covered sheet-pile walls and mechanical characteristics of rods are analyzed,seismic mechanisms and deformation characteristics of covered sheet-pile quay are studied in detail and the seismic effect is confirmed under different parameters.Finally,the reasonable seismic design values of design parameters are presented.The achieved results may serve as reference for the seismic safe design of covered sheet-pile quays.