To provide a structure of a plasma torch in which a sound joining can be realized at a low cost at the joining part of a tip nozzle and an inner and an outer cylinder in the nozzle cylinder of the plasma torch.

An electrode end for generating plasma arc 8 is provided at the center part of a plasma torch 1 in the plasma torch 1 for discharging a gas for plasma formation, and a nozzle cylinder 2 is arranged by surrounding the electrode end for generating arc 8. The nozzle cylinder 2 has a tip nozzle 6, a nozzle outer cylinder part 3, and a nozzle inner cylinder part 4, and the nozzle outer cylinder part 3 is constructed of a nozzle outer cylinder 3a and a joining member 3b. In this construction, the joining part of the tip nozzle 6 and the joining member 3b is joined by silver brazing under reduced pressure and the joining part of the joining member 3b and the nozzle outer cylinder 3a is joined by welding. Furthermore, the nozzle inner cylinder part 4 is constructed of a nozzle inner cylinder 4a and a joining member 4b, and the joining part of the tip nozzle 6 and the joining member 4b is joined by silver brazing and the joining part of the joining member 4b and the nozzle inner cylinder 4a is joined by welding.