To clarify the living conditions and development trend of the Populus euphratica population in the desert hinterland natural oasis, we analyzed the influence of the difference in groundwater depth condition on the age structure and renewal succession of the P. euphratica population. We selected the P. euphratica forest in the Daliyabuyi Oasis, lower reaches of the Keriya River, as the research site. The age structure characteristics were analyzed and the update dynamics on the sequence were predicted by classifying the age structure and groundwater depth gradient as well as quantifying the individual competitiveness. The results show that: (1) the age structure of the P. euphratica population in Daliyabuyi Oasis has a weak growth trend as a whole, but there are great differences among different habitats, and the updating capability of P. euphratica in most areas is relatively weak. (2) There is a power function relationship between individual competitiveness and age structure, the competitive relationship that can be maintained becomes more simple and the proportion of young stands with lower competitiveness decreases with the increase of groundwater depth. (3) The normal renewal succession of the P. euphratica population can be ensured when the water depth is less than 6 m, while the groundwater depth more thant 6 m will make the P. euphratica population lose the component of young forest, and showing an obvious declining trend.