Abstract: On the basis of analyzing hydrogeological conditions, the paper discusses the water filling factors and determines three ways that the water flows into the mine. According to the way that water flows into the mine through water flowing fracture zones, the paper uses simple hydrology geology test method and upward inclined drilling two-end ponding water conducted high observation method to study the development laws of water flowing fractured zones, determines that the crack injection-production ratio is from 8.3 to 8.8, and finally the paper constructs the BP neural network model of water fracture zones which includes mining thickness, mining depth, the thickness of the overlying strata, roof compressive strength, inclination, mudstone proportion six impact factors. The measured datum show that the model has better practicability. The results provide the basis for safety mining and the setting of waterproof coal pillar under large water.