PURPOSE: To make a sucking device compact, to enlarge a range of action of welding work and to improve maintenability by supplying compressed air to a suction pipe to cause it to generate process of absorption.

CONSTITUTION: When a trigger 9 of a welding torch 3 is pulled, a wire 6 is supplied from the end of the torch 3, and at the same time, a switch 15 becomes ON to operate an electromagnetic valve 14. The compressed air sent with pressure in a compressed air hose enters into an air suction bag 10 through the electromagnetic valve 14, and causes process of attraction. By this function, the process of attraction works in a suction cylinder 17 mounted on the outer circumference of a nozzle 8, and welding fume generated under it and such fume as sealed gas blowed out and going to disperse in the air and the like are absorbed in an air suction pipe 10 through a suction hose 18. The absorbed fume is delivered from an exhaust outlet 20 through the suction hose 18 and passed in the air suction pipe 10.