Abstract:An investigation was carried out to study the variation of 6 phenotypic traits of stem form and branching structure from 1904 accessions of Hevea brasiliensis germplasm conserved in Jinghong, Yunnan Province.The results showed that there are abound genetic diversity in Hevea brasiliensis germplasm conserved in Jinghong(1.6731-0.2604).The diversity stem straightness is the highest,than stem devergence, branch diameter, branch whorl,branch angle, while branch extension is the lowest.The minimum value of distribution frequency of relative traits ranged from 2.92% to 8.05%, and the maximum from 39.64% to 93.37% among the 6 traits. Based on the Euclidean distance, 1904 accessions germplasm were divided into 5 groups at 1.05 thresholds by UPGMA and divided into 5 groups at 1.45 thresholds by furthest-neighbor cluster analysis. Abundant phenotypic variation existed in the populations of germplasm resources.