Abstract: 【Objective】In order to distinguish the taxomomy of "Yihuang wild rice" that found in Yihuang county, Jiangxi Province in 1999. 【Method】The botanical characteristics of "Yihuang wild rice" by genus and species were retrived, at the same time, the tubercle characters on lemma in "Yihuang wild rice", O. rufipogon, O. officinalis, O.Meyeriana, and O. granulate also were observed by scanning electron microscopy. 【Result】The retrieval result by genus showed that "Yihuang wild rice" is Leersia Soland. Ex Swartz., not Oryza L., Hygroryza Nees and Chikusichloa Koidz. The retrieval result by species showed that "Yihuang wild rice" is L. sayanuka Ohwi, not L. hexandra Swartz., L. japonica (Makino) Honda and L. oryzoides (L.) Swartz.. The results of the SEM observation of tubercles on lemma showed that the tubercle characters on lemma of "Yihuang wild rice" is belong to inlaid-silica-peak type, differing from the three wild rices existed in China, O. rufipogon, O. officinalis, O.Meyeriana, as well as O. granulata, but similar to L. tisseranti. It gives a proof of the above retrieval result. 【Conclusion】It is speculated that "Yihuang wild rice" does not belong to Oryza L., but belongs to Leersia sayanuka Ohwi.

Key words: Yihuang wild rice, Taxonomy, Tubercle characters on lemma, Wild rice, Leersia, L. sayanuka Ohwi