Abstract: Through the study of lithology, recharge, runoff and drainage conditions in Ordovician limestone aquifer, we carry on feasibility analysis for the floor at fully mechanized working face affected by mining and water inrush coefficient and other comprehensive factors. In the process of working face advancing or before mining, we adopt geophysical prospecting, drilling, chemical exploration, and find out the geological structure of working face roof and floor, and analyze the laws of water bursting in water-conducting, which ensures the smooth and safe mining of working face.