Abstract: A new mathematic model based on Luikov's diffusion theory was presented to simulate the drying and tempering process of rough rice. The moisture distributions at different distance of intermittent drying were obtained. And also the tempering effects on the subsequent drying period were analyzed. A comparison between the simulated values and the experimental values showed that the maximum differences in the moisture content of grain was at 1. 5 %. The model has been used to analyze the intermittent rough rice drying successfully.