An investigation was conducted on the population structure and dynamics of Alsophila spinulosa in Mount Emei with the onthespot investigation method, adopting height class (H) to represent age class. By establishing a static life table, plotting a population survival curve, analyzing the survival function, we characterized the population structure and dynamics. In addition, by constructing a time series prediction model, was also examined and predicted the current survival status and future development trend of the population, respectively. Results showed: (1) the population structure of A. spinulosa in Mount Emei was irregular pyramidal. The middleaged individuals (0.6 m＜H≤2.1 m) shared 58.5% of the total population amount, while, the young (H≤0.6 m) and the elder ones (H＞4.8 m) only accounted for 12.7% and 1%, respectively. Young individuals were deficient, and the maintenance and development of the population structure mainly relied on the middleaged and adult (2.1 m＜H≤4.8 m) individuals. (2) The dynamic index of population age structure quantity with future external disturbances considered V′_pi=3.027＞0 showed an overall, but gradually declining growth of the population. (3) The population survival curves tended to be DeeveyⅡ type, as the mortality rate remained stable among the 1st-6th class, but increased acutely from the 7th class to the 8th class, which indicated the following dynamic features of the A. spinulosa population: early stage, declining; middle stage, stable; and last stage, recession. (4) Time series prediction revealed that after a short period of growth, the population of A. spinulosa would gradually decline, and the species might even become endangered if not protected. In conclusion, the research showed the loss of young individuals and failure of population replenishment is the main cause of A. spinulosa population’s endangerment in Mount Emei. Our suggestions including the establishment of local nature reserves, artificial breeding, and the advances of research into highefficient breeding techniques are proposed for the rejuvenation and renewal of A. spinulosa there.