Abstract: Typical surveys were carried out in May-June, October-November 2020 on spontaneous vegetation in different habitats in Xixi National Wetland Park (hereinafter referred to as Xixi Wetland), Zhejiang province. The result demonstrated that there were 273 species of 86 families of spontaneous plants. Arbor and shrub habitats had the highest and most stable diversity. The communities tended to be woody in arbor and construction habitat, and herbaceous in grassland and farm land. The seasonal variation of community components was the smallest in arbor and the largest in farm land and shrub. Cluster analysis on communities resulted fifty groups, among them, the dominant groups and pan-habitat groups had greater advantages in the spatiotemporal niche competition. Season, habitat and location had obvious selection effects on the single season group, single habitat group, hygrophytic group and mesophytic group.