Abstract: The plants of Pugionium Gaertn. were biennial plants in Cruciferae, morphological characteristics of cotyledon epidermis of four species in Pugionium Gaertn. were investigated by using scanning electron microscope(SEM). The results showed that the bulliform cell was distributed in adaxialepidermis and abaxial-epidermis of Pugionium Gaertn. cotyledon, which was protuberant, large and parallel arraying, and its density in adaxial-epidermis was higher than that in abaxial-epidermis, and the density of P.cornutum(L.)Gaertn was minimum, the density of P.dolabratum var. was maximal, the length of the bulliform cell of P.dolabratum Maxim. in adaxial-epidermis was larger than that in abaxial-epidermis, but the rest was contrary. The P.cornutum(L.)Gaertn, P.dolabratum Maxim. and P.dolabratum var. platypterum.H.L.yang had ridgy epiderial cells in adaxial-epidermis and abaxial-epidermis, with sinking stoma, but guard cells of P.calcaratum Kom. were below the even epidemic cell, with sinking stoma. The study could clarify that the same characteristic of microstructure of cotyledon epidermis of Pugionium Gaertn, and the difference in species, so it could provide morphological evidence for stress resistance and taxonomy.

Key words: sandy vegetable, Pugionium Gaertn., cotyledon epidermis, micromorphology