Based on deep buried depth, complex hydrogeologic condition and possible Ordovician water outburst of Yangdong Mine, horizontal directional well technology is needed before mining, coal seam floor aquifer and Ordovician aquifer vertical water structure were explored, guiding pre-grouting reinforcement. Different sidetracking technology was adopted based on different geological structure, fault, collapse column, structural development scale and characteristics of rich water conductivity were got, which completed the shortages of geological exploration and provided reference for exploration and control of mine construction and prevention and treatment of ash water.