The coastal Vatica forest in Hainan is a special type of tropical rainforest. The methods of landscape patch analysis included both quantitative mathematical modeling and qualitative comparison—8 kinds of species-area mathematic modeling curve and community characteristics. Shannon-Wiener index,Pielou indexãevenness index, importance value, layers′ Gleason index were used to analyze species-diversity. The aim of the study was to reveal the minimum landscape patch and species constitution of this forest type in Shimei Bay. This circumstance differed greatly from that of mountain rainforest in Hainan Island. The study revealed that minimum landscape patch of coastal Vatica forest in Shimei Bay was lowest in the global rainforest types. On the other hand, natural rainforest climax community, with low species diversity and salient single dominant community characteristics, was also located in Shimei Bay, Hainan Island.