With the increasing mining intensity and depth of coal mines in North China Coalfield, the shallow coal resources were increasingly depleted, and the liberation of deep coal resources in coal mines was imminent. Among them, the Ordovician limestone karst groundwater with high water head and large flow rate had become the most important factor restricting the lower coal group mining. The previous coal mine water damage prevention and control methods could not meet the needs of the lower coal group. Therefore, the coal seam floor grouting reinforcement technology under regional control was proposed. Based on the existing engineering examples, this paper studied the key technologies such as stratum, structural condition analysis, grouting transformation layer selection, full angle change rate and target front distance design, and conducted comprehensive control combined with directional drilling technology and grouting technology. The results showed that the technology ensured the construction quality and control effect of grouting reinforcement project, eliminated the hidden danger of water damage, and realized the safe mining of working face.