Abstract: Aiming at the problem that floor was prone to occur water inrush accidents in №.2₁ coal seam of Lugou mine filed,hydrogeological conditions and water damage characteristics of the mine were analyzed.The principle of water control,"near drainage and far blocked,combined drainage with blocked,the reasonable design of drainage system and equipped with drainage ability,separating water and coal as far as possible,keeping the clear water into the water warehouse",was put forward on the basis of the analysis.The method of combining deep grouting reinforcement with shallow drilling drainage was taken,which achieved remarkable control effect.