A metering valve includes: a high-pressure partition wall to isolate a storage region from an atmospheric pressure space; an internal partition wall arranged inside the high-pressure partition wall and forming a metering chamber partitioned from the storage region; a stem linearly movably supported and biased to be positioned at an origin position; a first seal hole penetrating the high-pressure partition wall to extend over the atmospheric pressure space and the metering chamber with a first seal portion linearly movably supporting a first intermediate portion; a second seal hole penetrating the internal partition wall to extend over the metering chamber and the storage region with a second seal portion linearly movably supporting a second intermediate portion; and a starting-end-side stem internal flow path formed inside the stem and extending from a starting end of the stem to the second intermediate portion, the starting end being always positioned in the storage region.