The China endemic species Woonyoungia septentrionalis community structure was investiged at Dahuangni, Luocheng County, Guangxi Province.The results showed that there were 129 vascular plants belonging to 57 families and 103 genera in plots of 1 200 m2, which dominated by Tropical genera. The community could be named as Woonyoungia septentrionalis Gomphandra tetrandra Castanopsis hickelii Community according to species importance value. The community could be vertically divided into three layers: tree layer (including 3 sublayers), shrub layer and herb layer, and interlayer species were rich. The mesophanerophytes and microphanerophytes made up 67.18% in life form, and the mesophyll and microphyll were dominate. The frequency distribution from the Raunkiaer was A＞B＞C＜D＞E, accounted for 41.09% in class A. The structure of Woonyoungia septentrionalis populations indicated that young trees were the main component of the community. Woonyoungia septentrionalis is a critically endangered species which must be protected by in-situ conservation，and establishment nature reserve as soon as possible.
