Abstract: The problem of water inrush from open pit in karst area seriously affects the normal production of mines, which not only brings huge economic burden to mining enterprises, but also destroys the ecological environment, and may cause disasters or production safety accidents. Curtain grouting technology is now more and more used in mine water prevention and control projects in karst areas. Taking the water inrush control project of a limestone mine in South China as an example, based on the basic situation and water inrush situation of the mine, the curtain grouting seepage control system is implemented step by step at the mining pit boundary to achieve the control goal. According to the project implementation, the evaluation content, evaluation standard and evaluation method are put forward, and the curtain wall quality and water plugging effect are evaluated in detail respectively, and the control effect is remarkable.