The anatomical characteristics of rhizome, lateral root, stem, leaf, petiole, ovary and leaf epidermis about Atractylodes japonica Koidz. ex Kitam. and A. macrocephala Koidz. were investigated to estimate these taxonomic values. The cross sections of stem and ovary were very similar to two species, therefore these characters were not useful for delimitation of two species, but the size and distribution numbers per 100${mu}{ extrm}{m}$$^2$of oil cavites in rhizome, the shape of leaf and petiole in cross section, the size of leaf epidermal cell and distribution numbers per 100 ${mu}{ extrm}{m}$$^2$of stomata were differ from two species, therefore these were thought to be useful characters for delimitation of two species.