Abstract: Considering the practical production figures and block mechanism analysis of Well WAA-1, the coiled tubing acid washing measure for removing pollution is proposed, and then the operation background, project design, operation process as well as effect evaluation of coiled tubing acid washing treatment are illustrated in this paper. By adopting the way of tripping the coiled tubing and controlling the lift speed and injecting rate, the acidizing fluid can be distributed equally in the horizontal interval. While wash head impulse vibrate, it will produce pressure agitation to screen pipe to wash deeply and remove damage.