The invention discloses a multi-station synchronous transmission structure of an upper disc of a polishing machine. The multi-station synchronous transmission structure comprises the upper disc, a plurality of mechanical arms evenly arranged on the upper disc and a driving mechanism arranged in the center of the upper disc; and the mechanical arms are connected with the driving mechanism through transmission mechanisms and are driven by the driving mechanism. By means of the multi-station synchronous transmission structure, the mechanical arms evenly distributed at multiple stations can be driven by one motor to swing synchronously, the equipment machining accuracy can be guaranteed, the polishing quality and efficiency of a machine tool are improved, and the multi-station synchronous transmission structure is suitable for part polishing, machining and the like of parts large in batch and high in shape and face quality requirement.