Abstract: Use of press-molded flanged glass envelope members each including a central hollow cylindrical portion enables fabrication of high output cold cathode gas laser tubes of reduced axial length with materially reduced cost of production. The cylindrical portion of one of the envelope members surrounds one end region of the capillary tube thereby to prevent discharge concentration on the adjacent end region of the cylindrical cold cathode while that of the other envelope member serves to support the capillary tube at about the middle of its axial length, eliminating the need for a "flaring operation" requiring highly skilled labor.