The invention discloses a punching device for electric wire threading slot punching. The punching device for electric wire threading slot punching comprises a rack, wherein an oil cylinder connecting bottom plate is fixedly arranged on the bedplate of the rack, a connecting strut is fixedly arranged on the top surface of the oil cylinder connecting bottom plate, an upper connecting plate is fixedly arranged at the upper end of the connecting strut, and a punching oil cylinder is fixedly arranged on the upper connecting plate; waste box adjusting motors are respectively fixedly arranged and vertical adjusting screws are hinged on the two sides plates of the rack, a waste box supporting plate is in threaded connection in the two vertical adjusting screws, the waste box supporting plate is provided with a stepped through hole, a waste box is inserted into the stepped through hole, the outer wall of the top portion of the waste box is provided with a radially extending supporting edge, and the radially extending supporting edge is inserted into the insertion section of the upper portion of the stepped through hole. The punching device for electric wire threading slot punching has the advantages that a wire threading slot plate can be automatically punched, the upward and downward adjustment of the waste box can be realized through the waste box adjusting motors, the waste can be collected in a unified manner and automatically falls down to the ground, and the waste box does not need to be manually lifted for discharging.