Abstract: This invention relates to a gas discharge hollow cathode tube for laser using metal vapors having a vacuum compact housing where an anode and a hollow spiral cathode are mounted connected to a source of excitation, the hollow cathode contains an active metal medium, having evenly distributed apertures on the pipe's upper inner part, and resistance wire fitted inside the hollow cathode supplied from an electric source. This apparatus avoids the disadvantages of a similar gas discharge tube having metal in the cylindrical cathode where the metal vapors enter the discharge zone uncontrollably, causing metal accumulation in some zones which thus partially covers the laser tube aperture, and because the high-level ionic metal laser levels are not efficiently excited as it operates under low voltages, it cannot be used for generation using easily fusable metals as the spiral cathode cannot be made of such metals. The invention also has improved stability and efficacy of the generation.