Based on the population life table and survival analysis theory, I used the method that space instead of time and piecewise sliding technology to create the timespecific life table of Populus euphratica population in the lower reaches of Tarim River. Then, I drew the survival curve and mortality curve of P. euphratica population, and analyzed the dynamic variation process. The results are as follows: （1）the survivorship curve of P. euphratica population was a concave; the death rate, which were all below 20% in Ⅰ-Ⅲ, increased rapidly from Ⅲ to Ⅷ and reached the peak at Ⅷ ageclass, and maintain above 50% after Ⅷ ageclass. （2）Cumulative mortality rate of P. euphratica population increased 75.79% from Ⅰ to Ⅷ ageclass; However, the cumulative mortality rate form Ⅸ to Ⅻ only increased 5.07%, that indicated there was a high death rate of seedling and sapling of P. euphratica population ; Hazard index, which was 0.142 3 at Ⅶ age, was reached 0.217 4 at Ⅻ age, which indicated that hazard index was increased along with the increase of age of P. euphratica ; The mortality density decreased 0.018 7 that was remarkable between Ⅶ age and Ⅸ age, explained that there was amount of P. euphratica died from Ⅶ to Ⅸ .（3）Spectral analysis of the population showed that the natural regeneration of P. euphratica population was a minor periodic change in Ⅵ age class, that perhaps be connected with the physiological property of P. euphratica and human disturbance.