Abstract:Based on the spot investigation, taking the height and ground diameter data as the basis, according to the age pyramid and the fitting equation of age structure, the age structure characteristics, growth status and development trend of the three typical populations of Kumtage desert were studied. The results showed that the age structure of H. ammodendron population was inverted “J” shape curve, and the population was currently in rising stage and was stability. The growth was limited because of their relatively small seedlings number. The age structure of T. taklamakanensis population showed a "bell" shape curve, and it showed similar stabile population characteristics. Bing of the very small number of seedling and the larger proportion of middle age class plants, the development of the population will tend to decline. The age structure of P. euphratica Oliv population has a certain peculiarities and showed a reverse "S" curves. The proportion quantity of middle class and older class plants maintained certain stability, and the large quantity of the small class plant make population has increasing potential. Their own age structure characteristics of three typical populations made them face the different degree threat of survival. So it was necessary to take different protection measures to maintain the population structure‘s stability and development.