The invention discloses a bridge top rotation body structure which comprises a rotation body component. Steel plates are paved in the rotation body component, a sliding way is vertically arranged in the rotation body component, the top of the sliding way is positioned on the inner top surface of the rotation body component, the bottom portion of the sliding way is arranged on the inner bottom surface of the rotation body component, a sliding body is horizontally mounted on the sliding way, protection plates are connected among two sides of the sliding way and the rotation body component and obliquely arranged on the sliding way and the rotation body component, bearing plates are mounted on the lower surface of the protection plates, the top of the bearing plates is integrally connected with the protection plates, the bottom of the bearing plates is fixed on the inner bottom surface of the rotation body component, the bottom of the rotation body component is connected on a rotating seat, and the rotating seat is connected with the rotation body component through a rotating rod. The bridge top rotation body structure can effectively bear local pressure, overall stress demand is met, pier top operating space is enlarged, safety is improved, design difficulty of the rotation body structure is greatly reduced, structure reliability can be effectively improved, tonnage of the rotation body is decreased, and engineering cost is reduced.