Abstract: This paper deals with a comparative analysis for the first time on two species of the genus Uncaria of the Rubiaceae, Uncaria rhynchophylla (Miq.)Miq. ex Havil. and Uncaria rhynchophylloides How, in external characters, ornamentation of seed -coat under scanning elec -tron microscope, internal structure of petiole and stem, and alkaloid content. As a result we support the view that Uncaria rhynchophylloides How be retained as a separate species.The content of rhynchophylline is lower than inspecting quantity, U. rhynchophylloides How can not be used as medicinal plant U. rhynchophylla (Miq.)Miq. ex Havil.

Key words: Uncaria rhynchophylloides How, U. rhynchophylla (Miq.)Miq. ex Havil., external character, internal structure, chemical composition.