Drying is the key process in chemical, food and other related industry process. Corns, fruits, and vegetables are usually used as porous medium in drying process. The parameters of modeling are very important because the simulation results are decided by them. The intrinsic permeability is the property of the porous medium that is should be gotten by accurate method. Based on the theory of heat and mass transfer, a coupled model for the porous medium vacuum drying process is constructed. The model is implemented and solved using COMSOL software. The parameter sensitivity analyses of intrinsic permeability were then examined. The temperature, pressure and moisture characteristics were shown.