Abstract: The description of well-aquifer system is one of the most important and fundamental problems in hydrogeological sciences.In the past years,numerous hydrogeological modelers used "line-sink" of "heat conduction" to describe a well.In order to do so,one needs to determine the discharge or head distribution of the linear sink/source in advance.Up to now,the validity and applicability of such a description is not proved rigorously.Chen in 1992 presented the concept and theory of a "Seepage-pipe Coupling Model" and "Equivalent Conductive Coefficient",which solved the problem of obtaining the multi-layered hydrogeological parameters and could predict the drawdown of multi-layered geological structures in mixed pumping tests.This model was suitable to simulate horizontal wells,artesian wells,mixed observation wells and so on,and was gradually developed to a groundwater flow model with triple media of karstic tube-fissure-pore. This method was validated by in-situ tests and several case studies,and was also verified by experimental simulation.