The invention provides a test sample gas sealing device for a gas-enriched coal rock gas solid coupling state impact test so as to research the impact mechanical property of a gas-enriched gas coal rock. The device comprises a support, a gas sealing storehouse, a sealing storehouse cover, a transmission rod connecting end, an incident rod connecting end, a transmission rod, an incident rod, an O-shaped sealing ring, a YX-shaped sealing ring, an incident rod connecting end and storehouse cover fixing bolt, a transmission rod connecting end and sealing storehouse fixing bolt, a gas inlet hole, a gas outlet hole, an electromagnetic adjusting control valve, a gas inlet adjusting gas valve, a gas tank, a gas outlet gas valve, a gas suction pump, a high-frequency gas gas-pressure sensor, a super-dynamic gas pressure acquisition instrument, a gas pressure monitoring instrument, a computer, a balance adjusting bolt and a fixing bolt. By adoption of the device, the gas content of a test sample is constant in the impact stress wave loading process in the gas-enriched gas coal rock impact test process. A unique test device is provided for research on the mechanical property of the gas coal rock.