Abstract: Radial and tangential gas permeability of Masson pine wood were measured respectively in this paper.The results show that radial permeability and tangential permeability of masson pine decrease gradually from sapwood to heartwood and increase with moisture content decreasing and radial permeability is greater than tangential permeability.The effect mechanism on wood permeability and different properties are discussed and analyzed.The main flow paths in the radial direction are wood rays and horizontal resin canals,the flow path in the tangential direction is unaspirated pits on tracheids wall and cross fields. Permeability increases with moisture content decreasing due to void space increasing in wood.