Theoretical prediction usually provides basic understanding and guidance to establish reasonable technology in the production process. A partial differential equation was used in this study to predict heat transfer time between the surface and core layer of wood during heat treatment. The prediction was compared with the result of an experiment that was performed on Chinese poplar lumber with various thicknesses of 20 mm,40 mm and 60 mm. The times for the core temperature to reach to 100 ℃,130 ℃,and 180 ℃ were recorded and compared with the predicted values. The comparison of the results showed that the theoretical predicted times matched the experimental values very well.