Abstract: Xishan coal electricity group Malan coal mine who's main slope bottom water warehouse layout within the Ordovician top water-resisting layer. Water warehouse floor is the Ordovician limestone Fengfeng Group and by serious threat of the Ordovician limestone aquifer. In order to eliminate the water inrush hazard, in view of water warehouse floor rock deformation characteristics and closer, high water pressure of aquifer, with large amount of water, adopt new design materials for the water warehouse floor of grouting reinforcement, which achieved good results. New design materials is a new design of reinforced concrete cover who's covered in water warehouse floor. Using the shallow hole grouting low-voltage alternating with deep hole high pressure grouting filling way. The new method increased with the integrity of the surrounding rock and closed grout, making the floor more stable.