The invention relates to a roller shell surfacing welding positioner counterweight device. The device comprises a counterweight block, a pick hook, a pick beam, a positioner, a roller shell, positioning columns and a device foundation, wherein the two ends of the positioner are provided with supports, the supports are fixed on the device foundation, the positioner is arranged on the device foundation through the supports and connected with the supports through rotating shafts, and the positioner turns along the rotating shafts; and one side of the positioner is connected with the roller shell,the other side of the positioner is provided with a positioner cross beam, the pick beam is fixedly arranged on the positioner cross beam, the top end of the pick beam is provided with the pick hook,the pick hook is internally provided with the counterweight block through a connecting belt in a hung mode, slide blocks are arranged on the two ends of the counterweight block, the positioning columns are arranged on the device foundation, and the slide blocks are clamped between the positioning columns in a sliding mode. The device can improve the safety and stability of the equipment.