Abstract: By testing the main physical and mechanical properties of four typical thick-growing woody bamboos in Yunnan, Dendrocalamus giganteus, D. brandtsii,D. membranaceus and Bambusa lapidea, it was recognized that the maximum moisture content, air-dried density, absolute density and basic density were different not only from the species but also from the different position at a bamboo culm and that there was no marked deviation for the moisture content at air-dried slate and the density at maximum moisture content. The shrinkage, esp. the radial shrinkage, varied soundly with the different species of bamboo, but no evident difference appeared along the longitudinal direction. The radial shrinkage was greater than the tangential shrinkage; and the tangential shrinkage at the outside part of a culm was greater than that at the inner part. The variability of both longitudinal crushing strength and tangential bending strength is larger in different position of the culm than in the different species. All this difference should be considered as an important part to be played in designing the composition, technology and quality of the panels for the thick-growing species of bamboo as a raw material.