Abstract:The phenotypic diversity analysis of 14 phenotypic traits was conducted in 246 sesame germplasm resources from different sources in China. The highest genetic diversity index(2.06)of plant height and number of capsules per plant were detected,while the coefficient variation of capsule number was ranking first with 60.73% in 14 phenotypic traits. By the principal component analysis of 14 phenotypic traits,the top five principal components(yield factor,capsule factor,plant type factor,hairy factor and nectary factor)contributed to 67.527% of phenotypic variation. Cluster analysis assigned five groups of the sesame germplasm resources when the genetic distance was 8.0. The accessions within group Ⅰ showed potential on yield increase,while the accessions with high-pillar and high-yield of excellent material with good comprehensive traits were resided in group Ⅱ. Group Ⅲ was consisted of the accessions showing high-yield and branched. The accessions showing high-rod and multi-grain were resided in group Ⅳ,while the accessions showing short-rod and short-internode were found in Group V. By taking use of the geographic information,sesame populations of different sources were classified into 4 groups,including Group Ⅰ(Henan,Hubei,and Hebei),group Ⅱ(Shanxi),group Ⅲ(Shaanxi)and group Ⅳ(Chongqing). The highest values on average of coefficient of variation and the genetic diversity index were found in accessions of group Ⅱ(Shanxi). Taken together,this study provided a theoretical basis for future utilization of sesame germplasm resources in parental selection and modern variety breeding in China.