The utility model discloses a cost control switch, which comprises a box body of which the upper end is provided with a cable interface for a cable to pass through, and a waterproof part which is positioned above any one of the cable interfaces and is sleeved on the cable, the inner wall of the waterproof part is tightly attached to the cable, and the lower end face of the waterproof part is fixedly connected with the upper end face of the box body to achieve sealing. The inner wall of the waterproof part of the cost control switch provided by the utility model is tightly attached to the cableto prevent rainwater falling from high altitude from flowing downwards along the cable, and the lower end of the waterproof part is hermetically connected with the upper end surface of the box body to prevent rainwater accumulated on the upper end surface of the box body from flowing into the box body along the gap between the cable and the cable interface. Rainwater is prevented from entering the box body above the cable interface through the waterproof part, so that the phenomenon of repeated tripping and closing caused by damp short circuit of electrical apparatus elements in the box bodyis avoided, and the use effect of a user is improved.