Based on the three-dimensional wave physical model test,this paper studies the mechanical characteristics of the berthing pier under the cover of the slope dike,and analyzes different influences of wave overtopping height and various wave directions on the wave force acting on the breasting dolphin protected by the rubble breakwater.The results show that:1)When the wave propagates to the rubble breakwater,some of the wave is breaking and over the breakwater impacting on the breasting dolphin directly,while the other part of the wave will bypass the breakwater and forms the diffracted wave behind the dike to impact on the breasting dolphin.2)Due to the violent vertical wave impact,the vertical wave force acting on the berthing pier is larger than the positive wave force and transverse wave force.3)With the increasing wave overtopping height,the vertical wave force and positive wave force on the breasting dolphin increase significantly,but transverse wave force has no obvious increased trend.Meanwhile,the bigger wave overtopping height will also cause the ratio of vertical wave force to transverse wave force to increase.4)Different from no significant distinguish of wave force between positive wave and oblique wave for small wave overtopping height,oblique wave can produce larger wave load when the wave overtopping height is large.As well,the oblique wave can strengthen the wave diffraction and decreases the rate of positive wave force to the transverse wave force.