The invention discloses a lifting device with a double-layer lifting function, belongs to the technical field of mechanical devices and aims to solve the problems of structural redundancy and low safety of the existing lifting device. The lifting device comprises a guide structure, a first lifting mechanism and a second lifting mechanism, wherein a first rotary support of the first lifting mechanism is connected to a base of the guide structure; the second lifting mechanism is connected to the base of the guide structure through a second rotary support; and the first rotary support and the second rotary support are respectively coaxial with a center hole of the base of the guide structure and fixed on the upper side and the lower side of a flat plate of the base respectively to be used forproviding power for the movement of the first lifting mechanism and the second lifting mechanism. According to the lifting device, a ball screw pair is used as a transmission component and the solidball screw and the hollow ball screw are used to drive a double-layer lifting mechanism in an ingenious manner of being coaxially cooperative, thereby greatly simplifying a transmission system and solving the problems of structural redundancy and huge volume of the traditional lifting machine. Besides, double locking ensures the safety of the lifting device reliably.