Abstract: Filed trials at different altitudes and consisting of different fertilization treatments were conducted using different aged young trees of Taxus chinensis var. mairei at different growing seasons. The effects of age, organ, position, and season of harvesting, as well as cultivation method on the taxol content in T. chinensis var. mairei seedling in short-rotation plantation were also studied. Significant differences in taxol content were demonstrated among young trees of different ages, organs and positions. The taxol content in branches and leaves of 1—2 years old seedlings was significantly higher than that in 3—4 years old seedling. The taxol content in root bark was the highest, followed by the stem bark and branch bark. By contrast, the taxol content in leaves and stem xylem was the lowest. Among different parts of crown, the taxol content in the upper branches and leaves was the highest, followed by the middle and the lower part. For different growing seasons, the taxol content in branches and leaves was relatively higher in January, May and the period from September to December, whereas it was low in growing stage from July to August, when the temperature was hot and the light radiation was strong. Considering the necessity of trunk-cutting-off, the appropriate harvesting seasons for T. chinensis var. mairei were November, December and January. The altitudes of planting sites had significant effect on the taxol content in the branches and leaves of young trees, as the higher altitude was beneficial to the biosynthesis of taxol. It was demonstrated that organic fertilizers could be applied to promote the growth and biomass accumulation of T. chinensis var. mairei seedlings, without the impact on the biosynthesis of taxol.