The features of ecological restoration， ornamental garden， and forage values are possessed by pennisetum plants. Research on the genetic diversity of pennisetum germplasm resources can be conducted to offer theoretical basis for new variety breeding， development， and utilization. In this study， 48 Pennisetum germplasm resources were used as materials. Through phenotypic trait determination and SSR molecular marker technology， phenotypic characteristics， genetic diversity， and population structure were systematically evaluated. The results showed that the coefficient of variation for four phenotypic traits was observed to range from 28.10% to 96.92%， with a genetic diversity index of 2.49 to 2.83， indicating rich diversity. Plant height was found to be significantly positively correlated with leaf width， while tillering was observed to be significantly negatively correlated with plant height and significantly negatively correlated with leaf width. Phenotypic clustering was determined to be divisible into three categories. A total of 122 alleles were detected from 20 primer pairs by SSR markers， with an average of 6.10 per pair. Shannon’s diversity index was measured to range from 0.35 to 0.64， polymorphism information content was measured to range from 0.25 to 0.79， and the average genetic distance was calculated to be 0.43. UPGMA clustering was divided into three to five categories as the similarity coefficient was increased， and the population genetic structure was determined to be divisible into three groups with significant differences in genetic background among groups. In this study， the genetic diversity and population structure of 48 Pennisetum germplasm resources were elucidated， and a theoretical foundation was laid for subsequent germplasm identification and new variety breeding.

Pennisetum spp.  /  Phenotypic diversity  /  SSR marker  /  Genetic diversity  /  Population analysis  /  DNA fingerprinting