The present paper deals with the anatomy of vegatative organs of Gymnotheca Decsne. Many significant differences between the genus and the other genera (Saururus L. and Houtuynia Thunb.) of the same family have been discovered in our study. On the contrary, the genus and Zippelia Bl. of the family Piperaceae have many anatomical characteritics in common. The genera Gymnotheca Decne. and Zippelia Bl. are therefore considered intermediate between the families saururaceae and Piperaceae from anatomical point of view.