Taxus wallichiana var. mairei, a rare and endangered species, ranks as the first class on the List of the Important Wild Plants for Conservation in China (first passel). By applying Ripley’s point pattern analysis, we examined the spatial distribution patterns and the associations among different age-classes of T. wallichiana var. mairei ex-situ population from the western foothills of Zijin Mountain to elucidate its spatial distribution characteristics. The results showed that individuals of ageclass I presented a random distribution at small spatial scales (1-4 m) and large scales (10-15 m), but with an obvious clumped distribution at medium scales (4-10 m). At all scales, individuals of age-class Ⅱ performed an evident clumped distribution. However, individuals of age-class Ⅲ had a random distribution. Overall, the ex-situ population presented a clumped distribution. The spatial association of individuals between age-classes I and Ⅱ had a significantly positive correlation both at small spatial scales (1-4 m) and large scales (10-15 m), whereas there was no significant correlation at the rest of scales. Individuals of age-class I had a negative correlation with those of ageclass Ⅲ at the spatial scales of 6-13 m, but they did not have an obvious correlation at the rest of scales. In contrast, age-class Ⅱ had no obvious correlation with age-class Ⅲ at all scales. Considering that most young individuals mainly presented clumped distribution and that the intraspecific association of this ex-situ population was similar to that of wild population, all efforts that can minimize human disturbance and protect suitable habitats of the secondary forest near the mother trees in Zijin Mountain should be made to increase the population size and distribution area.