Abstract: A metal vapor laser generating apparatus comprising a laser fine tube having Brewster windows at the ends and containing rare gas, an anode provided near one end of the fine tube, a vessel housing metal which is to be forwarded into the fine tube as vapor and ionized there by discharge, and a branch tube having its one end connected to the fine tube at a point adjacent to the other end of the fine tube. A cathode is provided at the other end of the branch tube and a large number of fine slits are bored through the wall of the branch tube at the central portion thereof, the slitted portion being surrounded by a sealed outer tube loaded with an adsorbent for adsorbing the ionized metal. The size of the slit is adjusted to permit passage of the ionized metal, but not to cause a discharge leakage.