[Objective]In the paper the study aimed to study the species diversity and stability of Tsuga tchekiangensis communities in Mang Mountain nature reserve.[Method]A set of data total 30 plots were used.[Results]The results showed that:(1)The differences of the richness indices,diversity indices and evenness indices among different communities were great,the diversity indices and richness indices of the plant communities were obviously affected by the type and structure of the communities,the more complicated of the structure,the bigger of the diversity indices and richness indices and the smaller evenness indices included;(2)There was a greater variation in species diversity among different life form,however,it was found that this variation was not always statistically significant;(3)The results of community stability calculated by improved M.Godron method were very low,furthermore,there is not a clear relation between the stability and the communities,this showed that the five types communities were all in the process of succession in various degree.[Conclusion]This study is important to protect Tsuga tchekiangensis community in Mang Mountain nature reserve.