Abstract:A series of techniques including the analysis of variance, X2-test, Ochiai, Dice and Jaccard indices were used based upon a 2×2 contingency table to determine the interspecific association of the 13 dominant species in a subtropical Castanopsis fargesii forest in the Jinyun Mountain of China. We expressed the results in the forms of semi-matrix, complete-matrix and constellation figures. Our results indicate that the interspecific association of the dominant species in the subtropical Castanopsis fargesii can be adequately interpreted by using the techniques mentioned above. To be specific, the analysis of variance can be used to explain the overall association of all species; the X2-test can be used to describe the statistical significance and the property of the interspecific association; and the Ochiai, Dice and Jaccard indices can be employed to show to what degree a pair of species is associated. The result shows that the interspecific association is very complicated. The relationship between Castanopsis fargesii and Elaeocarpus decipiens is significantly positive. Castanopsis fargesii is significantly negatively related with Gordonia acuminata or Castanopsis carlesii var. spinulosa. The probability of the presence of a specific accompanying species will be high if all the constituent species in a community are closely evolutionarily related, have similar environmental requirements, and respond to the environmental factors with a similar manner. However, the species association properties can not be determined based on the above analysis.