Sluice project is an important part of the flood control system of rivers and lakes in China. Once damaged，it will endanger the safety of downstream dams and people's lives and property. Aimed at the dynamic response of bent column and machine room at the top of gate pier，this paper explores the influence of gate pier height on the dynamic response of gate pier top structure by comparing the dynamic response differences of a certain sluice project at different pier heights. The research results show that the damage at the bottom of the gate pier will gradually decrease with the increase of the gate pier，and the damage at the bottom of the bent column at the top of the gate pier will gradually increase with the growth of the gate pier；The top machine room is prone to relatively obvious whiplash effect under dynamic action，and the displacement is much larger than the bottom characteristic point；The height of the pier has little effect on the dynamic response of the bottom plate；The deformation result of the hoist beam is greatly affected by the gate pier，and the displacement increases with the height of the gate pier to a limited extent；The displacement of the top machine room is greatly affected by the damage of bent column，and the whip effect is obvious.