Abstract: The paper examines the application of flow equation for single-phase slightly compressive fluid in a medium with double porosity to its numerical solution to the one dimensional radial flow,two dimensional areal flow and axialsym metrical flow field using cylindrical coordinate,in order to simulate and study the pressure build-up curve for the double porosity media.The last two problems are solved by using the finite element method.From analyses of the results of simulation,the author puts forward the concept of source and sink,based on the difference between pressure build-up rates in the fracture and the block system,in different parts of the well drainage area.Physical explanations are given to the form of pressure build-up curve for the double porosity media in the context of the dynamic equilibrium of the total amount of flow in the source and sink areas.