Abstract: To understand the impact of Ageratina adenophora invasion on plant diversity in the Baihualing area of Gaoligong Mountain, a sampling method was used to investigate the species and quantity of herbaceous and shrub plants in 3 plantation plots around Baihualing in the Baoshan section of Gaoligong Mountain, which were invaded by A. adenophora. The species composition, community structure, species richness index, diversity index, and evenness index of the community were analyzed. The results showed that a total of 93 plant species were collected from 3 plots, belonging to 26 orders, 38 families, and 83 genera; the invasion of A. adenophora caused a significant decline in the number, frequency, abundance and other characteristics of plant community species in the sample plot, and the species richness index, Simpson diversity index, Shannon−Wiener diversity index, Pielou evenness index of the invasion plot decreased significantly; with the increase of months, the Simpson diversity index and Shannon−Wiener diversity index of invasive areas showed no significant changes, while their species richness index and Pielou evenness index increased significantly in October; the community structure of the invaded area has substantial changes, with Urtica fissa, Artemisia caruifolia, Arthraxon hispidus, and Digitaria sanguinalis exhibiting better species abundance and competition. These results enrich the list of grass and shrub plants in planted forest in Gaoligong Mountain, provide plant diversity data support for the ecological safety assessment of Gaoligong Mountain, and provide a reference basis for the next step of prevention and control of A. adenophora.