Taking Fagus lucida community in Kuankuoshui National Nature Reserve in Guizhou Province as the research object, based on field investigation and applying the method of quantitative ecology, the community characteristics and species diversity of Fagus lucida in the reserve are studied using quantitative ecology, this will inevitably provide a theoretical guidance for the monitoring of plant community dynamics and the conservation and management of Fagus lucida community in the reserve. The results show that there are 62 families, 111 genera and 165 species of vascular plants in the plot with an area of 11700m², including 4 families, 6 genera and 6 species of pteridophytes and 58 families, 105 genera and 159 species of seed plants. Among them, monospecies and oligofamilies (2-5 species) are dominant, and their sum exceeds 85% of the total families. In addition, there are 6 genera and 15 species of plants in Rosaceae, occupying the highest proportion of all families, followed by Lauraceae and Fagaceae. In terms of the structure of the genus, the single genus is absolutely dominant, reaching 70.27%, with the largest number of species of alum and raspberry, each with 6 species. Although Fagus lucida was dominant in the community, the age class structure shows an abnormal trend of double peaks, and the population shows a declining trend. From the overall trend, the community species diversity index is tree layer > shrub layer > herb layer; species richness index is shrub layer > tree layer > herb layer; evenness index tree layer > herb layer > shrub layer. Except that the seedlings and young trees of Fagus lucida are concentrated in some areas, the number of seedlings and young trees in most areas are small. This, coupled with the strong disturbance of Chimonobambusa utilis under the forest, leads to a large proportion of large-diameter plants and a declining age structure, so it is difficult to maintain population stability in the future. This implies that we should strengthen the protection of Fagus lucida. Therefore, it is suggested that the seedlings of Fagus lucida should be nurtured and managed reasonably. In the management and management of the forest, the forest of Fagus lucida can be moderately disturbed when it grows to a certain stage, which will be more beneficial to the regeneration, growth and development of Fagus lucida forest.