The morphology of leaf abaxial epidermis of 21 species of Festuca was examined under light microscope and electron microscope.The results showed that:(1)the species of Festuca had Festucoid type epidermis.The leaf abaxial epidermis of Festuca were characterized by long-tubular or short-tubular long-cells with markedly sinuous walls or few straight walls,elliptic or crescentic or subsquare short-cells distributed solitary or in pairs,rare or one or more rows stomata,parallel-sided or dome-shaped subsidiary cells,frequent or infrequent prickle-cells,subsquare or elliptic or crescentic or horizontally-elongated sinuous costal silica-cells.There were abundant variations of epidermal features within the genus Festuca.(2)The morphology of leaf abaxial epidermis was conducted by UPGMA analysis.Two major branches formed in the UPGMA tree.The clade Ⅰ included the species with rare stomata and frequent prickle-cells,species of subgen.Festuca constituted the clade Ⅰ.The clade Ⅱ included the species with one or more rows stomata and infrequent prickle-cells.The second clade was comprised of Subgen.Schedonorus,Subgen.Subulatae,Subgen.Drymathele.