Taking the corn material in bin as the study object, a pore network model for the corn drying was developed by applying the theories of drainage and percolation through porous media and transport-process. Various factors for the drying process, such as the heat and mass transfer in grain itself, vapor-phase convection, temperature gradient, as well as physical structure characteristic were considered into this model. Five independent variables were involved in this model, which was able to describe the drying process of corn material more effectively than the traditional drying model. Moreover, the physical structure characteristic parameters of corn material, such as porosity, pore size distribution and so on, as the model parameters, were input the model directly to predict the drying characteristic of corn material.