Abstract:84 quadrats from 5 vertical transects on Luhuitou fringing reef are investigated in detail using video-quadrat and indoor-interpretation methods. The results show that: (1) The reef consists of 69 species of hermatypic corals belonging to 24 genera and 13 families which are unevenly distributed in abundance. (2) Among all the corals, Porites lutea is the most dominant species with importance value percentages up to 36.62%; Porites and Acropora are dominant genera, with importance value percentages as 43.85％ and 22.88％, respectively. (3) There exist distinct spatial differences in coral communities: both the coral covers and coral diversity indexes in the northeastern transects are higher than those in the central and southern transects. (4) Coral communities also show remarkable zonal characteristics, with less coral species occurring in reef flat than in reef slope. The importance value percentage of the sole dominant coral genus, Porites, is over 50%, while in the reef slope, the importance value percentages are 28.33% for the first dominant genus Acropora and 2671% for the second dominant genus Porites. Our further analysis suggests that the spatial and zonal differences of coral diversity pattern are correlated with both natural environmental changes and human activities. The shallow water reef flat frequently exposes at low tide and receives more anthropogenic influences (including dredging and trampling) than the deep water reef slope. Thus, the coral community in the reef flat is not as well developed as that in reef slope. The relatively poor coral covers and coral diversity indexes in the central and southern transects are closely related to heavy human activities around these sites, such as aquaculture, fishing and coastal sewage. Therefore, the impact of human activities must be taken into account when developing strategies for the protection of this coral reef.