A gas transfer type fine powder quantitative feeding system comprising: a humidifying chamber for humidifying a carrier gas; and a gas transfer type fine powder quantitative feeder that quantitatively feeds a mixed fluid of the carrier gas and fine powder to a fine powder using device by feed of the carrier gas from the humidifying chamber, wherein the gas transfer type fine powder quantitative feeder comprises: a fine powder storage container that stores the fine powder; a housing that stores the fine powder storage container in a gas-tight manner; a feed port that feeds the carrier gas to the housing; a flow rate adjustment mechanism that adjusts a feed amount of the carrier gas to the housing; a feed nozzle that feeds the fine powder from the fine powder storage container to the fine powder using device entrained with the carrier gas; a position detection sensor for detecting a relative position between the feed nozzle and the fine powder surface; a driving part that moves the feed nozzle in an up and down direction; and a humidity measuring sensor for measuring humidity in the housing; and wherein the humidifying chamber comprises: a water tank that stores liquid for humidifying the carrier gas; an ultrasonic vibration mechanism for atomizing the liquid; and a humidity control mechanism for controlling humidity in the housing in conjunction with the humidity measuring sensor. a humidifying chamber for humidifying a carrier gas; and a gas transfer type fine powder quantitative feeder that quantitatively feeds a mixed fluid of the carrier gas and fine powder to a fine powder using device by feed of the carrier gas from the humidifying chamber, wherein the gas transfer type fine powder quantitative feeder comprises: a fine powder storage container that stores the fine powder; a housing that stores the fine powder storage container in a gas-tight manner; a feed port that feeds the carrier gas to the housing; a flow rate adjustment mechanism that adjusts a feed amount of the carrier gas to the housing; a feed nozzle that feeds the fine powder from the fine powder storage container to the fine powder using device entrained with the carrier gas; a position detection sensor for detecting a relative position between the feed nozzle and the fine powder surface; a driving part that moves the feed nozzle in an up and down direction; and a humidity measuring sensor for measuring humidity in the housing; and a fine powder storage container that stores the fine powder; a housing that stores the fine powder storage container in a gas-tight manner; a feed port that feeds the carrier gas to the housing; a flow rate adjustment mechanism that adjusts a feed amount of the carrier gas to the housing; a feed nozzle that feeds the fine powder from the fine powder storage container to the fine powder using device entrained with the carrier gas; a position detection sensor for detecting a relative position between the feed nozzle and the fine powder surface; a driving part that moves the feed nozzle in an up and down direction; and a humidity measuring sensor for measuring humidity in the housing; and wherein the humidifying chamber comprises: a water tank that stores liquid for humidifying the carrier gas; an ultrasonic vibration mechanism for atomizing the liquid; and a humidity control mechanism for controlling humidity in the housing in conjunction with the humidity measuring sensor. a water tank that stores liquid for humidifying the carrier gas; an ultrasonic vibration mechanism for atomizing the liquid; and a humidity control mechanism for controlling humidity in the housing in conjunction with the humidity measuring sensor.