Abstract: In order to explore moisture transfer law during larch timber drying process, three major diffusion PDE solution methods were used to analyze bound water transfer. One dimensional redial unsteady diffusion experiments for larch timber specimens with thickness of t0 mm and 20 mm were conducted. The parameters for drying kinetics curves were determined. Three kinds of analytical solutions for diffusion differential equation were obtained. The diffusion coefficients data of different solution procedures were compared. The influence mechanism of technique factors and material characters on moisture diffusion were determined. The results showed that under 50%-55%relative humidity, conditions, diffusion coefficients increased with temperature increasing. Among the three solution procedures, the linear function relationships between diffusion coefficients and experimental temperatures of Stature’ s method is the most notable one. In drying experiments with temperature of 80℃, when the equilibrium moisture content (EMC) decreased, the diffusion coefficients increased greatly for all three solution methods. Under the same drying conditions, diffusion coefficients of 20 ram specimens are all bigger than those of the 10 mm specimens’ for three solution methods. This change trend became even more remarkable with the temperature increasing. Below FSP, drying diffusion coefficients decreased exponentially with wood initial moisture content decreasing. It was coincided with basic descriptions of thewood bound water activation energy theory.