Abstract: Xiaowutai Mountain, located at the junction of the Taihang, Yanshan, and Hengshan ranges, represents a typical temperate montane forest ecosystem in North China and serves as an important ecological barrier for the Beijing–Tianjin–Hebei region. To fill the gap in systematic vegetation survey data, we conducted a plot-based survey during the 2025 growing season following unified technical protocols. A total of 67 plots were established along an elevation gradient and across different slope aspects to record community structure, species composition, and environmental variables; vegetation types were then classified and named, and the records were integrated into a vegetation plot dataset for the Xiaowutai National Nature Reserve. We documented 321 vascular plant species belonging to 197 genera and 69 families, with Asteraceae, Rosaceae, and Poaceae as the dominant families. By life form, there were 225 herbs (70.1%), 58 shrubs (18.1%), 23 trees (7.2%), and 7 species of ferns and lianas combined (2.2%), plus a single subshrub species. The vegetation was categorized into three vegetation formation groups, seven vegetation formations, and 36 associations, which together essentially cover the spatial distribution range of the major vegetation types in Xiaowutai Mountain. This dataset provides reusable baseline information for vegetation classification, community comparisons, and conservation zoning in Xiaowutai Mountain.

Key words: Taihang Mountain, Plant alliances, community structures, Species composition, vertical zonation spectrum