Abstract: This peper deals with the analyses of correlations among 23 dominat species of Nanmu (Phoebe bournei) community at Luoboyan Reserve by means of 2 ×2 contingency table and calculation of association coefficients. percentage co-occurrence and x 2. Most associations emerge to be low. Furthermore, the authors have also analysed the association between Nanmu and other associated species by calculating the t-test of correlation coefficients. These species of peitive associations are different from those selected ones according to the association coefficient and x 2. Compared with the associations among four pairs of related species in different sample areas, the authors concluded that quadrat sizes are the most important factors effecting the result of association measurement.