Abstract: Laixin iron ore is a mine of heavy-water karst.In the early development period,the mine was excavated mainly by sewer drainage,along with local water plugging to prevent and control water.The result showed that this method failed to control the underground water level to safety water level for mining and unconspicuous effective.In order to avoid the occurrence of catastrophic water damage,the underground curtain grouting near ore body was implemented.The application of grouting in ore vein by horizontal water prospecting drilling,roof encryption and group of hole grouting with appropriate parameters,made the water plugging very effective.The practice showed that the underground curtain grouting near ore body technique can be applied to prevent the damage of inrush water for mine of heavy-water karst,and thus it will benefit the society,economy and environment.