The invention discloses a hydraulic crane and a use method thereof. The hydraulic crane comprises a base, a storage box, a clamping and fixing assembly, a lifting assembly and a damping assembly; thestorage box is fixed to the top of the base through welding, the clamping and fixing assembly is arranged on the storage box, the lifting assembly is arranged on the other side of the top of the base,the damping assembly is arranged on one side of the base, the clamping and fixing assembly comprises a sliding block, a thread rod, a limiting rod, a first straight gear, a servo motor, a second straight gear, a rotating shaft, a thread hole and a through hole, the servo motor is arranged on one side of the storage box, an output shaft of the servo motor is connected with the rotating shaft through the coupler, one end of the rotating shaft penetrates the inner wall of one side of the storage box and is connected with the second straight gear, and the second straight gear is located in the storage box. According to the hydraulic crane, the position of the sliding block is adjusted, a transport object is clamped, damping is facilitated, object collision is prevented, and damage is avoided.