This paper describes a simulation model of drying of wood particles. The model is based on coupled moistureand heat balance equations and solved by using the finite-difference method. There are balances for absorbedwater in the wood, water vapor, air and heat; and a Darcian equation for the flow of humid air. The developedmodel predicts the drying course for varying drying conditions and materials; in this report it is applied tosawdust drying. The simulation shows fair agreement with the experimental data, though factors such as theintrinsic mass transfer coefficient for the evaporation and the thermal conductivity for the air and wood mixtureare possible to optimize further. Predictions of drying times, moisture content and temperature in the materialand bed pressure drop are obtained with the model. As in the experiments, the model shows a quit thin dryingzone characterized by large temperature gradients. These gradients require a very fine division in cells in thenumerical calculations to properly represent the coupled processes. A typical calculation of a drying processduring a few hours with 100 cells requires around 10 min computer time on an ordinary PC.