The invention discloses a lifting automatic centering holding clamping mechanism. The lifting automatic centering holding clamping mechanism is characterized by comprising a supporting frame (1); the two ends of the supporting frame (1) are each connected with a rail (4), the two ends of each rail (4) are each provided with a sliding block (3), and holding clamping bases (2) are connected between the corresponding sliding blocks (3) of the two rails (4); each holding clamping base (2) is movably connected with a holding clamping plate (9), each holding clamping plate (9) is connected with a first air cylinder (6), and a connecting rod mechanism (7) is connected between the two holding clamping bases (2); and a guide rail (5) is arranged between the two rails (4), a sliding block (10) is arranged on the guide rail (5) and connected with the connecting rod mechanism (7), the connecting rod mechanism (7) is formed by two connecting rods hinged through a connecting shaft, and the sliding block (10) is connected with a second air cylinder (8). The lifting automatic centering holding clamping mechanism is simple in structural principle, low in manufacturing cost, small in occupation space, high in safety and reliability, convenient to maintain and beneficial to application and popularization, and a box conveying line is simplified.