The utility model discloses a special drying protecting device for a gas humidity sensor. The drying protecting device comprises a measuring chamber provided with a sensor mounting opening in one end, wherein the measuring chamber is connected to a six-way valve, and is provided with an air inlet end and an air outlet end; the air inlet end and the air outlet end are respectively connected to the six-way valve; the six-way valve is simultaneously connected to a dryer, an air intake pipe and an exhaust pipe. The device disclosed by the utility model can effectively protect the gas humidity sensor so as to keep the sensor away from influence of water and corrosive gas in a storage process; the device is simple in structure, low in cost, free from special precision machining, simple to manufacture and mount, good in sealing and reliable in performance; the dryer is not in direct contact with the measuring chamber, so as to prevent the situation that dust drops caused by vibration or aging of an adsorbent to penetrate through a separation net so as to contaminate the sensor; the dryer, which is an independent part, is connected to a pipeline, and is easy to change in case that the adsorbent is saturated and becomes ineffective; under a protected state, the air intake pipe is directly communicated with the exhaust pipe.