The invention provides an anti-dumping ladder. An anti-dumping mechanism is arranged; the anti-dumping mechanism comprises a supporting seat, a driving mechanism and hoops; the supporting seat is positioned at the end part of a vertical side rod; the driving mechanism is positioned on the supporting seat; the rear parts of the hoops are connected with the driving mechanism to achieve the lateral drive of the hoops through the driving mechanism; the front clamping openings of the two hoops are relatively arranged on the two sides of a wire pole, and the tightening and relaxation of the wire pole are achieved by the driving of the driving mechanism. According to the anti-dumping ladder, operators can clamp the wire pole in the process of using by setting the anti-dumping mechanism, the inclination and overturn of the ladder in the process of using can be effectively prevented, meanwhile the anti-dumping mechanism can be applied to wire poles with different diameters, and thus the operation is safer.