The stomatal structures of leaves (bracts or fruits) from 20 genera and 29 species (9 genera and 11 species of subfamily Saniculoideae, 11 genera and 18 species of basal subfamily Apioideae). The results show that: (1) three types of stomata, anomocytic, anisocytic, and paracytic. The stomata in tribe Saniculeae of Saniculoideae are anomocytic (35%-75%) and anisocytic (25%-65%) (in the total number of stomata). The genus Eryngium has all three types, and only anomocytic type in tribe Steganotaenieae. In the basal taxa of subfamily Apioideae (except Bupleurum) the stomata are more anomocytic (75%-100%) and less anisocytic (5%-25%). （2）The stomatal features studied support to place Arctopus in Saniculeae and to move Choritaenia to Apioideae confirmed by molecular data. (3) The stomata structures of Saniculoideae are similar with those of Apioideae and Azorelloideae, but differ from Mackinlayoideae.