Provided is a device for processing an antistress cone of a main insulation layer of a cable. The device includes a support, a clamping unit, a cutting unit and an infeed unit. The clamping unit is mounted on the support and configured to clamp a cable. The cutting unit is slidably disposed on the support, capable of cutting the cable in the radial direction of the cable, and capable of performing feeding in the radial direction of the cable to adjust the cutting depth. The infeed unit is connected to and capable of driving the cutting unit and configured to drive the cutting unit to slide in the axial direction of the cable so that the cutting unit performs feeding and cutting in the axial direction of the cable.