|The morphological characteristics and radial variation of tracheid of the "F24x那 1-1" of the genetically modified clone of Cunninghamia lanceolata in Kaihua County, Zhejiang Province were studied. The results showed that when the tracheid were in the young age, the length of the tracheid and the length-to-width ratio of the tracheid were smaller in the vicinity of the medulla. As the growth age increased, the index value increased significantly. The annual growth rates increased to the maximum value, and then tended to be stable or slightly decreased; the tracheid width, tracheal double wall thickness and tracheal wall cavity were consistent with the radial variation law. As the growth age increased, the index value increased first. After reaching the maximum value, it tended to be gentle or slightly reduced, and the variation range was small. The radial variation law of the basic density of Chinese fir was basically the same as the variation of the length of the tracheid. The basic density was the smallest in the second year, which was 0.283 g/cm3. As the age of the tree increased, the basic density gradually increased, reaching a maximum value of 0.348 g/cm3 at the 13th year. The study provides theoretical support for the precision processing of wood and genetically improved wood breeding.