Chusquea Kunth and Rhipidocladum McClure species (Poaceae, Bambusoideae, Bambuseae) are the only two genera of woody bamboos whose distributions reach the southernmost portion of the Andes mountain range. The identification of woody bamboos relies mainly on vegetative characters. In the present work, foliage leaf blade anatomy of Andean woody bamboo species occurring in Argentina and neighboring areas is described. Eight species are surveyed: Chusquea culeou E. Desv., C. deficiens Parodi, C. lorentziana Griseb., C. montana Phil., C. quila Kunth, C. valdiviensis Phil., Rhipidocladum neumannii Sulekic, Rúgolo & L. G. Clark and R. racemiflorum (Steud.) McClure. Leaf blade abaxial epidermal and cross section characters of each species are described and an identification key based on anatomical characters is provided. Anatomical evidence that support the idea of C. quila and C. valdiviensis as different species is presented and information on useful characters to distinguish between them is provided. Also, taxonomic position of R. neumannii is determined based on anatomical features. Finally, the taxa studied are compared in tables based on leaf anatomical characters of taxonomic value.