Abstract:To understand the characteristics of the community with dominant species of a invading injurious weed, Eupatorium odoratum, which is widely distributed in Guangxi Province, the floristic composition, geographic elements, life forms, species diversity in the community as well as community structure were investigated. There are 62 species of 58 genera in 38 families in seven plots with total area of 175 m^2. Most of the genera are of pantropical and Asian tropical comprising 15 and 8 genera, respectively. According to Raunkiaer's life-form classification, micro- and nanophanerophytes (48.39%), therophytes (17.74%) and hemicryptophytes (12.90%) are the dominants. Leaf characters in the community are mostly herbaceous, microphyllous, and of simple leaves or with entire margin. The community structure is simple, having only shrub and herb layers. Both probability of interspecific encounter index and Shannon-Wiener index of diversity in shrub layer are relatively high, suggesting that this community is relatively stable, and E. odoratum is at the stage of population establishment.