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Pterospermum kingtungense C.Y.Wu ex Hsue,which is endemic to China,is an endangered plant from the family Sterculiaceae.It is listed as a Grade Two endangered plant for state protection in the Red Data Book of plants in P.R.C.This species only exists in Jingdong County,Yunnan Province,Southwest China,and is distributed within an extremely limited range.This study was conducted to determine the status of the population,analyze the past population structure and forecast the future population dynamics of P.kingtungense.The size structure and height structure of the population of P.kingtungense were tabulated and analyzed.Based on these data,we estimated the values of parameters such as survival curve,mortality curve and life expectancy.The number of young individuals was larger than that of middle-aged and old individuals.The analysis of life table and survival curves showed that under environmental screening and human disturbance,the population had one peak of mortality in size class Ⅲ and only 23.57% individuals could survive from size class Ⅲ to size class Ⅳ.The life expectancy of P.kingtungense was highest in size class Ⅰ.The survival curve of the population belongs to Deevey-Ⅲ type.