Species composition and stand structures of 3 forest communities under different protection regimes in Nanling National Nature Reserve in Guangdong Province were studied. Three communities, i.e., Community Ⅰ, Community Ⅱ and Community Ⅲ, located at the experimental area, the buffer area and the core area，respectively, each represented by 30 plots, were surveyed and compared. The result showed that floral areal-types of the three communities were similar, which Pantropic, Trop. Asia (Indo to Malesia) and E. Asia & N. Amer. disjunct distribution types were dominant. And CommunityⅠshowed the least variety of floral areal-types. CommunityⅠ, with the least protection, had less species richness and DBH than the other two. Community Ⅱwith the medium protection had the biggest average DBH value. And Community Ⅲ with the highest protection had the highest species richness and the most variety of floral areal-types. There were significant difference in species richness and DBH among the three communities (P<0.001). It is difficult to conclude that species composition and structure with higher protection is better. Therefore, the management of the Nature Reserve should consider the local sustainability, make a good control of the human activities base on the local socioeconomic context to maintain the healthy of the community.