PURPOSE: To raise the gas discharging efficiency and provide an improved gas-filled discharge tube whose discharge properties and not deteriorated by elapse of time by keeping the diameter of the gas-filled tube large in the case that the gas-filled discharge tube is made compact.

CONSTITUTION: A gas-filled discharge tube is a tube prepared by air-tightly fixing a terminal plate 2, in which a discharge electrode is projected inside, at both end parts of aninsulating outer casing 1 and filling it with an inert gas and a gas sealed tube 3 is extended coaxially from the outside end face of the terminal plate 2 and at the same time, a plurality of gas introducing holes 2d, 12d to communicate the inner space 1a of the discharge tube with the inner space 3a of the gas sealed tube 3 are formed in the electrode pedestal side wall part or the circumferencial part at electrode position of the terminal plate. As a result, gas discharge is carried out efficiently.