To clarity the species composition and interspecific association of Ephedra equisetina communities in Wulu Mountain Nature Reserve, we carried out a series of typical sampling investigations. Based on the 2×2 contingency table, we used variance ratio(VR), χ₂test, Pearsons correlation and Spearmans rank correlation to analyze the interspecific association among 25 dominant species in Ephedra equisetina communities. Results showed that: (1) 25 dominant species were significantly positively correlated, indicating a relatively stable succession status in the communities. (2) The χ₂test, Pearsons correlation and Spearmans rank correlation analyses among the 300 speciespairs of the 25 dominant species showed that 141, 128 and 129 speciespairs were positively correlated, 132, 151 and 134 speciespairs were negatively correlated, and the positive and negative ratios were 1.07, 0.85 and 0.96, respectively. (3) According to the species adaptations to the environment and the leading ecological factors, in combination with principal components analysis, the 25 dominant species were divided into four ecological species groups. The result showed high interspecific association among the E. equisetina communities. The communities also showed relative stability in species composition and development of community structure.