PROBLEM TO BE SOLVED: To provide a convenient and safe regulator for compressed gas cylinders, when an abnormal pressure is generated, automatically releasing it.SOLUTION: The compressed gas regulator includes: a body, the inside of which is partitioned by a valve seat with a valve hole, into a primary side and a secondary side, and that has a compressed gas outlet in the secondary side and an abnormal pressure relief hole 14 at a part close to a handle with respect to the outlet； a sleeve having a gas passage and provided inside the primary side of the body； a pin 2 that is axially movably supported in the gas passage and is energized in a direction of closing the valve hole, with the tip thereof penetrating to the secondary side via the valve hole； a pin presser 4 that slides inside the secondary side so as to press the pin in the opening direction while retaining airtightness between the relief hole and the valve seat by a packing 13； and a pressure regulating spring that energizes the pin presser in the pin opening direction by an operation of an opening/closing handle in the opening direction. The pin presser is displaced to a position where the packing goes beyond the relief hole, by the abnormal pressure against the energizing force of the pressure regulating spring, so that the abnormal pressure is released from the relief hole.
