Abstract:Based on the 2 vegetation-types, 9 formations and 16 associations of the tropical rain forest in Xishuangbanna, which have been summarized, revised and renamed by the author, this paper deals with the statistical data of 434 main plant species of 16 association tables of the ecological structure features. A computer data base of all species has been established with the fea-tures of their presence in vegetation types, structure layers, life form types and the ecological morphological features of their leaves. Based on the data base, it has summarized the diversity fea-tures of ecological structures such as the horizontal and altitudinal structures, the spectrums of life form, leaf scale, leaf pattern, leaf texture.leaf margin, leaf apex in the tropical rain forest of Xishuangbanna . These features are similar to those of the typical tropical rain forest of Sutheast Asia, but the tropical rain forest of Xishuangbanna has several north-margin features. As for the features of ecological structures of all plant species, there are more diversity features in this transitional north-margin rain forest than in the typical ones.