B Based on 6 quantitative traits and 23 qualitative traits, the phenotypic variation, genetic diversity, and cluster relationships were investigated in Erianthus rockii wild species. The results showed that the variation coefficient of the 6 quantitative traits ranged from 12.72%~22.38% among the 51 materials, brix trait had the greatest coefficient variation of 22.38%, stalk diameter as the next of 22.27%, and lamina length was the smallest of 12.72%.Furthermore,the genetic diversity was abundant in internode colour exposed, however, stalk shape, bud shape, internode shape, growth crack, inflorescence shape did not segregate. Moreover, the cluster analysis indicated these progenies could be divided into 4 groups and 5 subgroups. Genetic diversity and cluster analysis would be helpful to utilization of the materials in breeding and gene discovery.