The utility model discloses a rapid water seal device for a gas pipeline. The rapid seal device for the gas pipeline is suitable for gas seal and comprises a gas pipeline water seal device body. A high-level water storage device is arranged above the middle rear portion of the gas pipeline water seal device body and comprises a rotating shaft, a water storage tank body and an electromagnet, wherein the rotating shaft is installed on a machine frame, the water storage tank body is installed above the rotating shaft and swings frontwards and rearwards around the rotating shaft, the electromagnet is installed on the portion, located at the rear end of the water storage tank body, of the machine frame, and the rotating shaft is located behind the gravity of the water storage tank. The gas pipeline water seal device body comprises a water seal trough, a floating ball water tank which is arranged at the rear end of the water seal trough and located below the front portion in the water storage tank body and a floating ball installed in the floating ball water tank, wherein the top of the floating ball is provided with a floating ball ejector rod, the upper end of the floating ball ejector rod vertically penetrates through a top plate of the floating ball water tank, and an overflowing pipe communicated with the water seal trough is arranged on the middle upper portion of the floating ball water tank. The rapid seal device for the gas pipeline can rapidly inject water into the gas pipeline to cut off gas, can achieve automatic resetting, relieves the burden of operators, and guarantees the safety of a gas system.