In order to improve the level of the mine water prevention and control technology, the concept of key stratum water, patterns, classification, influencing factors and mechanism of key stratum water were introduced, aiming at two of the most common damage ordovician limestone water disasters and goaf water disasters waterproof technology related  were discussed. Finally, “drivage stage - before the mining face - mining face process” as coal mining industry process, prevention and control of water technology according to water-resisting layer mechanism was expounded as a whole.