Abstract: In order to reveal the response of terrestrial plant communities to pollution in the Three Gorges Reservoir area, we selected 32 sampling sites with similar environmental factors but different distances from the pollution source, a phosphorus chemical factory. A total of 284 vascular plant species were recorded in these sites, belonging to 182 genera and 76 families, including 35 tree species, 139 shrub species and 110 herbage species. Species richness and Pielou evenness index were used to measure species diversity. Species richness in polluted area was 32–67, while in control area it was 47–82. Pielou evenness index of tree layer was 0.1161–0.8509, while those of shrub layer and herb layer were 0.1763–0.3249 and 0.0443–0.2601, respectively. The results showed that both species richness and Pielou evenness index were influenced by the point source pollution. Species importance values showed significant differences between polluted area and control area. Dominance of different species had changed, and some species even disappeared under the pressure of pollution, indicating a process of species replacement in plant communities. Such species replacement can provide a scientific basis for species selection for restoration of human-damaged ecosystem. The natural regeneration of Quercus variabilis was insensitive to pollution, while Cupressus funebris was effected seriously. Therefore, the results implied that point source pollution in the Three Gorges area had a strong negative effect on the composition and diversity of terrestrial plant communities. Further study needs to be carried out to study the long-term succession of the plant communities.