Abstract: The textual research of the names and things, especially searching Chinese plants denomination is the recognized difficult problem in the traditional linguistics. The crux of the matter is to search the scientific ways of finding out the origin of the names and things from the point of the methodology. The article holds the idea that the method of searching meanings out of sounds, i.e. the compatative method linking to cognate words plays a very important role in the ancient Chinese plants denomination. This method can not only avoid making errors in sound-based word interpretation, but also distinguish the differences between the similar plants denomination, which is of the important value in analyzing the ambiguous ancient exegesis and the heterodoxy.