Abstract: Wood drying theury, i. e., Equilibrium Moisture Content (EMC), heat-transfer and moisture-diffusion, dryiug stress and strain etc. was widely applied in wood pretreatments, drying process, wood protection (storage, wood sterilization), wood-producls manufacturing and strength-design of wood-structure. Wood drying theory played an important role in improving wood drying, quality, reducing drying time, saving energy-consumption, preventing checks and deformations of wood-products and ensuring strength and safety of wood-structure.