Glycine tomentella, which belongs to Glycine subgenus of Glycine Willd., is a secondary protected wild plant in China. It is distributed in the coastal areas of Fujian and Guangdong and nearby islands. It is an important genetic resource for soybean breeding. In recent years, due toland development, the abuse of herbicides, environmental changes and many other factors in the distribution area, the population of G. tomentella has been affected to varying degrees. Therefore, it is urgent to clarify the plant composition and community structure characteristics of the community, in order to provide theoretical basis for the protection of the original habitat of the species. In this study, 50 G. tomentella plant communities were selected in the coastal zone of Fujian and Guangdong. The ecological data of plant composition, plant density and average plant height of 255 quadrats (1m×1m) were investigated, and the species diversity, interspecific relationship and niche characteristics of the communities were analyzed. The results showed that: (1) There were significant differences in the plant composition of G. tomentella community between Fujian and Guangdong provinces. A total of 166 species belonging to 138 genera and 48 families were recorded, including 123 species of herbaceous plants (74.10%); There are 53 species belonging to 45 genera, 23 families unique to Fujian Province and 70 species belonging to 64 genera, 27 families unique to Guangdong Province. There are 13 dominant species shared between the two provinces, and the composition of the primary dominant species also exhibits considerable differences.(2) The interspecific association degree of the community species in Fujian Province was higher than that in Guangdong Province, and the distribution of species was more uniform at the quadrat level. (3) The niche breadth of Imperata cylindrica and Cynodon dactylon in Guangdong Province was much higher than that in Fujian Province; The species with higher niche overlap between the two communities are completely different. This indicates that the niche characteristics of the same species exhibit geographical adaptability. (4) The results of overall and interspecific association analysis and interspecific correlation analysis showed that most species pairs showed no significant negative correlation, and the species were basically independent, and the communities in the two provinces were in an unstable state.