The invention discloses a pressure-adjustable gas storage container and full-automatic gas injection system suitable for an EAST Tokamak device. The pressure-adjustable gas storage container and full-automatic gas injection system comprises a gas storage container, a control cabinet, a full-automatic gas extraction and compensation valve, a piezoelectric-valve water cooling system, and a man-machine operation interface written by Labview. The gas storage container has a gas inlet for receiving gas and a gas outlet for outputting gas. Firstly, working gas goes from a compressing cylinder into the gas storage container via an oxygen pressure-reducing valve, with magnitude and stability of the pressure in the gas storage container being controlled by multiple valves. Finally, the working gas is controlled by a high-speed piezoelectric valve to enter a cellular nozzle via a one-way protection valve, so as to be sprayed out. An industrial control computer, an N1 board card, an electronic unit and a solenoid valve are installed inside the control cabinet. The piezoelectric-valve water cooling system is used to achieve the cooling and electromagnetic shielding effects which are required during installation of the piezoelectric valve inside a vacuum chamber. Finally, setting and real-time monitoring of an experiment system are realized by means of the man-machine operation interface written by the Labview.