Abstract: Fagus (Fagaceae) is a small genus with 11 monoecious tree species. Fagus lucida, occurring in high subtropical mountains, is an abundant deciduous species which forms an important component of mixed broad-leaved evergreen and deciduous forests. Using Braun-Blanquet and Fujiwara phytosociological meth-ods, we compared the F. lucida forests distributed in Mt. Nanshan，Mt. Fanjing，Kuankuoshui Nature Re-serve, and Mt. Badagong in order to protect remanet forests due to overexploitation. Based on data from 37 sites, three associations and six subassociations were identified. Comparing species composition and life-form structure of the associations, we found that the Yushanio basihirrsuto–Fagetum lucidae communi-ties in Mt. Nanshan and Sinarundinario chungii–Fagetum lucidae communities in Mt. Fanjing and Kuanku-oshui Nature Reserve had similar characteristics of mixed evergreen and deciduous broad-leaved forests,while Sinarundinario nitido–Fagetum lucidae communities in Mt. Badagong presented feature of deciduous broad-leaved forests. The DBH size classes of F. lucida in Mt. Nanshan and Mt. Badagong had an L-shaped distribution and a monomodal distribution, respectively. In Mt. Nanshan, F. lucida regeneration benefits from forest gaps but is hindered by dense bamboo. In Mt. Badagong, natural regeneration of F. lucida is poor although bamboo is scarce. Further researches is needed to explain this phenomenon.