Abstract: The authors attempt through the analysis of floral composition to demonstrafe that the main forest vegetation in southern Yunnan is a part of tropical forest in Asia. However, the forest possesses obviously local characters because of the distribution have reached the limited range of the latitude and a1titude. The northern limit of the tropical forest and its floral composition distributed in Yunnan has been identified by the general distribution regularity through the analysis of fifty common plants and some pure tropical families and genera. And all the plants here were incorporated into four disfributional types. i. e.

Key words: floristic, characteristics, Yunnan