Abstract: The Daxue Mountain in Zhenkang county is situated in the southwest part of Yunnan Province, occupying 24˚20′N, 99˚06′E. The evergreen broadleaf forests under study are well preserved. They are characterized by complexity of types, abundance of tree species and wide distribution in a wide range of altitudes (from 1900m to 2800m above sea level). They are typical mountain humid evergreen broadleaf forests in the subtropical region of Yunnan.In the paper, according to similarity in community structure, dominant species and habitat condition, these evergreen broadleaf forests have been divided into five community types, They are:1. Lithocarpus echinotholus-Ardisia crispa var. amplifolia community; 2. Cyclobalanopsis glaucoides-Vaccinium bracteatum community; 3. Lithocarpus echinotholus-Ophiopogon grandis community; 4. Lithocarpus echinotholus-Acer sikkimense var. serrulatum community; 5. Lithocarpus echinotholus-Tsuga dumosa community.Stratification in all these communities is obvious. The trees totaling 85 species may be divided into three layers. Some of these species have tropical origin, such as species of the Elaeocarpaceae, Sapotaceae and Proteaceae. The dominant species of tree layer are different from the other mountain humid evergreen broadleaf forests in other places of Yunnan. One of them is the Lithocarpus echinotholus, which is distributed widely in this region. The trees of the upper layer are always mixed with a few deciduous broadleaf trees and the Tsuga dumosa (an evergreen needle tree). Bamboo groves of the species synusia are conspicuous in the undergrowth, which also contains of Chimonobambusa and Pleioblastus. The herb layer is not well developed. The dominant plant lifeforms of this forest are the mesophanerophytes and microphanerophytes, which account for 62.5% of the forest. The trunks of big trees are round and straight, the bases of which often become little buttresses. The timber storage of this forest reaches over 260m3/ha. The natural regeneration of the dominant species is very poor under the canopy, but better at forest-windows or forest-edges.It is suggested that these kinds of evergreen broadleaf forest must be delimited into a natural preserve, so that they may present a principal scientific base for forestry research.