The invention discloses an aluminous gusset plate dismounting device. According to the technical scheme, the aluminous gusset plate dismounting device is mainly composed of a support, a hand wheel, a supporting rod, a guide clip, a lifting hook and a suction cup, a screw rod is arranged at one end of the lifting hook, a guide groove matched with the inner boss of the guide hole of the guide clip is formed in the screw rod, the screw rod is arranged in the threaded hole of the hand wheel, the boss on the guide hole of the guide clip is made to be clamped in the guide groove of the screw rod, the screw rod is made to axially move and not to rotatably move by rotating the hand wheel, the other end of the lifting hook hooks the suction cup, the lifting hook carries out vertical motion under the combined action of the driving of threads and the guide clip by rotating the hand wheel, and meanwhile the suction cup is driven to carry out lifting motion so as to dismount an aluminous gusset plate off a ceiling. The aluminous gusset plate dismounting device is simple in structure and convenient to use, the aluminous gusset plate will not deform and be damaged in a dismounting process, and the aluminous gusset plate dismounting device is suitable for household use.