The invention discloses a pipeline plugging device. The pipeline plugging device comprises a plugging plate and a connecting pipe. The connecting pipe is a steel pipe with one end provided with a flange. The connecting pipe is divided into an upper part and a lower part along the axis, wherein the upper part and the lower part are the same. The outer circle of a pipeline is sleeved with the connecting pipe. The outer circle of the connecting pipe is sleeved with clamps. The upper part and the lower part of the connecting pipe are locked through the clamps, and the angle of 90 degrees is formed between the joint of each clamp and the gap between the upper part and the lower part of the connecting pipe. The end, provided with the flange, of the connecting pipe is detachably connected with the plugging plate. The plugging plate is a circular steel plate. An annular groove is formed in one face of the plugging plate. A sealing ring is arranged in the annular groove. The section of the sealing ring is in a U shape. The pipeline is inserted in the sealing ring and is closely attached to the sealing ring. The pipeline plugging device is good in sealing effect, the connecting pipe is locked through the clamps, connecting is firm, the plugging plate and the flange of the connecting pipe are detachably connected, mounting and dismounting are convenient, repeated usage can be achieved, and the high-efficiency requirement for site construction is met.