An auxiliary disassembly device for disassembly of differentials comprises a mechanical portion and a hydraulic control portion. The mechanical portion comprises a disassembly mechanism final-assembly frame, a lifting sleeve, a center shaft, a bolt disassembling spanner and a lifting mechanism mechanical claw. The hydraulic control portion comprises an oil tank, a hydraulic pump, a hydraulic loop pipeline, a control valve set and a hydraulic cylinder. Damage-free disassembly of the differentials is realized by combined motion of the mechanical portion and the hydraulic portion, the center shaft is used for positioning and limiting, the bolt disassembling spanner is used for disassembly, and the lifting mechanism mechanical claw is used for grabbing a differential left shell to complete separation. The auxiliary disassembly device for disassembly of the differentials has the advantages that the problems of high labor intensity, low efficiency, large damage and primitiveness of differential disassembly means in manufacturing are solved, disassembly tools are integrated, and high efficiency, excellent quality, energy saving, material saving and environment friendliness are achieved.