PURPOSE: To attain cost reduction and reduce the size of a gas laser device by upgrading the fixing structure of a main electrode and a dielectric for a gas vessel and provide a high reliability-available gas laser discharging part by preventing the generation of creeping discharge and stabilizing the formation of glow discharge.

CONSTITUTION: A pair of main electrode 1 and 2 are laid out as opposed in a gas vessel 24 and fixed mechanically, forming a gas flow passage which includes a fan 21 and a heat exchanger 22. The main electrodes 1 and 2 are electrically connected to and fixed with dielectrics 10a and 10b. Furthermore, an insulator 17 covers the connection parts of the main electrodes 1 and 2 and the dielectrics 10a and 10b.