Abstract: CHY plug removing agent is developed to solve the problem of damage to the non-target zone caused by polyarylamide chromium gel(or gel).The agent is formed by combining inorganic material(possesses no damage to the oil reservoir) with a certain amount of catalysts.It can make the viscous polymer gel to dissolve rapidly into solution with the viscosity approaching that of water.The plug removal technique has the following characteristics:strong capability of removing plug,simple and convenient construction process and so on.Field application in Mengulin Oil Field shows that the effective percentage is 85.7%,the average incremental Oil of individual well is 660 t.