To solve the problem that if an emergency situation occurs when an operator performs a welding operation at a far distance from a welding power supply unit, the operator cannot quickly turns off a no-fuse breaker of the welding power supply unit.

In a welding machine including a no-fuse breaker, a welding power supply unit comprising a main circuit which converts commercial AC electric power into electric power suitable to welding and a main control circuit which controls the output of the main circuit, a welding torch, and a feeder which feeds a welding wire to the welding torch, the welding torch is provided with a microphone and the welding power supply unit is provided with a breaker drive circuit which turns off the no-fuse breaker. The main control circuit enters a speech recognition mode when an operation switch of the welding torch is turned on and off a plurality of times within a predetermined time so as to receives a predetermined speech picked up by the microphone through a connection cable and to turn off the no-fuse breaker by driving the breaker drive circuit when the sound volume of the speech is larger than a predetermined sound volume reference value.