Abstract: The Karst water inflow system is analysed by using systematical and cybernetic methods in this paper. Using the data of geologic configuration, hydrochemical field and isotopic field to synthesize the relevant information, we set forth the feeding source and range of karst pouring water and the relationship between supplying and draining in detail. The hydrogeological conceptual model and mathematical model for karst water inflow are estabilished more realistically, and its pouring process is simulated numerically. Finally, we study the mechanism of surface collapse caused by water pouring and put forth its treatment project for ensuring the safety of railway transportation.