Abstract: The present invention relates a weaving torch device for auto welding that can maintain necessary molten metal for desired welding such as welding by a person and provide the best welding beads, by locking a hinge pin and a conveying pin, which are provided to both sides of a weaving torch of a torch device connected to a welding machine, to a locking protrusion and a locking step of a hinge support member of a lower case in order to prevent left/right conveying while the weaving torch is automatically reciprocated up/down by operation of an electromagnet and a conveying spring.