Double surface polishing device

The invention provides a double surface polishing device, which can inhibit the degradation of operability when an upper fixing disc is trimmed and maintains a horizontal state of the upper fixing disc during the correction process. The double surface polishing device (1) utilizes a lower fixing disc (2) and an upper fixing disc (3) to polish two surfaces of a workpiece. The double surface polishing device (1) comprises a driving member (10), which penetrates the lower fixing disc (2) and rotates around the axis; a support mechanism (elevation actuator 9, opposite bearing 9b), which supports and hangs the upper fixing disc (3) in a way that the upper fixing disc (3) can swing and rotate; a hook (20), which is arranged on the edge of the central opening (3b) of the upper fixing disc (3); agroove part (11), which is formed in the circumferential surface of the driving member (10); wherein the hook (20) can be inserted into the groove part (11), when the relative rotation angle between the upper fixing disc (3)