Abstract: In recent years, due to its unique advantages, coiled tubing was introduced by many oilfields. It was widely used in oil and gas drilling, completion, workover, well logging and other construction operations, and played an increasingly important role in oil and gas exploration and development. It was introduced in this paper the principles, advantages and disadvantages, ground equipments and downhole tools of plug sweeping in coiled tubing. A case study was made in the well TK7219CH in the Tahe Oilfield in order to evaluate double pumping pressure, sweeping depth and working efficiency. The prospect and developing direction of this technique were also discussed.