The connection joint of pile-gravity composite structure is the place where the force is concentrated and the stress is large.The connection between the two materials is involved,which is the most critical and weak position of the structure.We use the ABAQUS finite element software to build the model of pile-gravity berthing dolphin,analyze the dynamic response of connection joint under impact load,and study the influence of different factors.The results show that the displacement and the peak value of tensile damage coefficient of the front row connecting joint of pile-gravity composite structure are greater than the latter two rows under the load of ship berthing.The maximum principal stress peak appears at the front of the joint of the front pile and the caisson.The buried depth of the pile should not be less than the pile diameter,and the effect of increasing the pile embedding depth on the stress characteristics of connecting joint is not obvious.Increasing the diameter of the pile is the most effective measure to improve the force characteristics of the joint.Increasing the caisson height is the most economical and reasonable to improve the force characteristics of the connecting joint.And the connection node with the structural measures can increase the force.