Micromorphological characters of leaf abaxial epidermis of 20 species, 6 subspecies and 2 varieties of Poa was examined by light microscope and scanning electron microscope, to infer its significance for classification of the genus Poa.The results indicated that: (1) the leaf abaxial epidermis of Poa were characterized by longtubular, fusiform or shorttubular longcells with straight or sinuous wall; presence or absence of shortcells in intercostal zone; frequent stomata and parallelsided or domeshaped subsidiary cells distributed in intercostal zone; presence or absence of pricklecells in costal zone, absence of pricklecells in intercostal zone; elliptic, reniform, crescentic, subsquare, horizontallyelongated sinuous or nodular silicacells distributed solitary or in pairs in costal zone; presence of crown cells in some species. (2) Variations of leaf epidermal features existed at the species level, such as shape and wall thickness of longcells, presence or absence of shortcells and its shape, distribution of stomata and shape of subsidiary cells, distribution of pricklecells, and shape of silicacells distributed in costal zone. The micromorphological study revealed that the characters of leaf abaxial epidermis could provide evidences for classification of the genus Poa. Moreover, the evidences of leaf abaxial epidermis confirmed the view that P. pratensis subsp. angustifolia and P. pratensis subsp. alpigena were the subspecies of P. pratensis subsp. pratensis.