Abstract:According to the field investigation and analysis of the Osmunda vachellii populations and communities from Mount Maluanshan in Shenzhen,the results indicated that:82 species of vascular plants, belonging to 48 families and 69 genera were found in the O.vachellii community,the floristic components of community was with an south subtropical property; The analysis for the age structure of the community showed that the main dominant species were stable populations,but the frequence index of community was A>B<C>D>E,which was different from the Raunkiaer’s frequency law,and was also different from those of montane rainforest of Hainan island; The percentage of tree height and individual number from O.vachellii population showed that those with a tree height 0.3-0.7 meters occurred a higher proportion,indicating the populations was in a bloom of development period;and the Simpson and Shannon-Wiener index of diversity is 16.42 and 4.56,while the evenness index for E and E′ is 0.33 and 0.83, respectively,which indicated the diversity and evenness index is closed to those of the climax community from typical subtropical evergreen broad-leaved forest. The study reveals the natural survival state of O.vachellii and provides protection and utilization data for O.vachellii.