The invention provides an automatically-controlled valve air reservoir comprising a valve connected with a movable cylinder. The air reservoir is characterized in that the air reservoir is connected with the movable cylinder, an air inlet and an air outlet are arranged on the air reservoir, an air control reversing valve and a one-way valve are arranged in the air reservoir, a three-way pipeline is arranged on the air inlet of the air reservoir, the air inlet is connected with the first end of the three-way pipeline, the one-way valve is connected with the second end of the three-way pipeline, the air control reversing valve is connected with the third end of the three-way pipeline, five air holes are arranged on the air control reversing valve, two of the air holes are connected with the air outlet through pipelines, other two of the air holes are connected with the movable cylinder, and the last one air hole is connected with the inner portion of the air reservoir. The air reservoir is reasonable in structure and obvious in effect; remote control of on-off of the valve, no air supply and on-off of the power supply control valve are well realized, and the air reservoir is applicable to the valve control field for flammable liquids, coal gas, flammable gas and harmful gas and liquid.