Abstract:  The first step of biomass pyrolysis corresponds to water evaporation. Thermal analysis instrument was used to determine the mass and heat change of fir wood during drying process. Non-isothermal drying kinetics model was derived to explore the mechanism of heat and mass transfer. The results show that moisture content decreases rapidly and weight loss peak appears at 80℃. Page model for non-isothermal drying kinetics can well simulate wood drying process and the drying activation energy is 12.6kJ/mol. Water and heat transfer have close relationship and the dry heat is mainly used for water evaporation. The value of heat requirement is 426kJ/kg and the simulated results show good agreement with experimental values.