The invention discloses a rapid plugging device for an oil and gas pipeline. The device is mainly composed of an upper shell and a lower shell, casting runners are arranged in the wall surface of theupper shell and the wall surface of the lower shell, and a welding groove and a temperature control groove are formed in the inner wall. According to the rapid plugging device for the oil and gas pipeline, when the device works, an annular cavity formed by the temperature control groove and the wall surface of a to-be-plugged pipeline is filled with a flame retardant through a liquid injection valve, then an aluminothermic reaction is carried out in a reaction funnel, generated metal liquid enters the casting runners from inlets of the casting runners under the action of gravity and finally fills the casting runners, and excess metal liquid flows out of overflow openings; after the metal liquid is cooled and solidified, a liquid discharging valve is opened to discharge the flame retardant;and finally, the liquid injection valve and the liquid discharging valve are closed, so that rapid plugging of the pipeline is completed. The rapid plugging device for the oil and gas pipeline has the advantages of being capable of realizing rapid plugging of the pipeline without stopping conveying of oil and gas, being firm in sealing, simple in structure, reliable in working and convenient andfast, being wide in application prospect and the like.