Abstract: The variation of wood structure in normal growth rings and false rings as well as the structure outwards from the pith to bark are investigated with four trees of Cunninghamia lanceolata at different age stages. The width of growth rings become gradually narrow with the increase of the tree-age after about ten years. False rings mainly appear in the wide growth rings near the pith,the number of which may be 1—3.It might be due to changes of temperature and moisture in the growing season.False ring always locates in the transition region from early to late wood within the growth ring.The sizes of wood elements in false ring are in the range of non-false rings. In normal growth rings,the average length of tracheids in late wood is 21% longer than that in early wood,the thickness of tangential cell wall of tracheids is 55% thicker,and the radial diameter of tracheid is 50% smaller than those in early wood. The size of wood elements in growth rings of the first 10th-15th outwards from the pith increases with the tree-age and undulates in rings there after. There are much warties on the inner surface of tracheid walls and bordered pit.