Abstract: The water inrush event of poor sealing borehole is a hidden danger in coal mine safety, and this paper presents a study on the tunnel in Buertai Coal Mine disclosing poor sealing drilling and inrush layer of water inrush boreholes. Identifying the water inrush layer and the water yield property of its lower confined water, in this paper, the drainage and pressure relief of the confined water was carried out by drillings, and the drilling hole grouting was used to transform the water-resisting layer of floor, and the safety technical measures for the safety of the poor sealing drillings in the working face have been developed. Through controlling hidden trouble from the source, the development of special measures to prevent and control the hidden danger, the working face smoothly passed through the poor sealing drilling area finally.