The westerlies lie in a transitional zone between two major climate systems of the north high latitude Hemisphere and the East Asian monsoon. Therefore, detailed studies on the evolution of the westerlies are key to investigating the past atmospheric circulation patterns,and hence to getting better understanding on the climatic forcing mechanism. The Ili Basin in the Xinjiang Province of Northwestern China is located in the Central Asian hinterland. The westerlies prevail this area perennially. Therefore, its widespread loess deposits in the alluvial terraces and piedmonts play an important role in understanding the evolution of climate change and atmospheric circulation in the westerlies. Considerable attentions have been attracted to loess deposits in the Ili Basin, especially on their origins, distribution, geochronology, magnetism and geochemical characteristics. However, the paleoclimatic significances of climatic proxies such as magnetic susceptibility and grain size remain unclear. Therefore,the evolution of climate change reconstructed from the loess deposit in the Ili Basin remains ambiguous, suggesting more studies with more proper proxies. In this paper, a typical loess/paleosol sequence (Zhaosu Poma section) from the Ili Basin has been chosen, and REE analysis is conducted to explore the climate change in this area since the Late Pleistocene. The Zhaosu Poma section (ZSP: 42.69°N, 80.25°E; elevation 1875m) is located in the second terrace of the Tekes River in the south Ili Basin. It is 6.85m thick and totally five pedostratigraphic units (S_0,L_1 L_1, L_1 S_1, L_1L_2 and S_1) can be identified. OSL dating show that the age of the bottom of this section is nearly 80ka B.P. The sub-samples for REE analysis were taken at 5cm intervals through the section and totally 138 samples were collected. Some typical samples were selected for size-differentiated REE analysis. The results show that REE values of ZSP are higher in fine particle sizes, and decrease with the increasing of particle size. However, the REE values show a weak correlation with the content of fine particles(<2mum),but no correlation with the content of coarse particles (>32mum). On the other hand, there is significant correlation between REE and Zr/Rb values which can be used to reflect the strength of the westerlies. These may suggest that the REE contents mainly document the change of the moisture and source material carried by thewesterlies. Therefore,climate change derived by the variation of the trajectory and intensity of the westerlies can be recorded well by the REE values in loess deposits in this area. The REE values in the ZSP section vary from 147mug/g to 181 mug/g, with an average value of 164mug/g since the Last Glaciations. The entire profile of REE can be divided into four stages taking 57ka B.P.,28ka B.P. and 8 ka B.P. as boundary. During 80 ~ 57ka B.P., theREE values are high at the beginning, with the highest value of 181 mug/g at about 80 ka B.P. It gradually decreases to the lowest value at about 57ka B.P. The REE values increase abruptly just after 57ka B.P. and then keep relatively stable until 28ka B.P.,with a range of 154~172mug/g. During 28~8ka B.P.,the REE values increase further to its highest average value (171 mug/g) of the four stages of the section. After 8ka B.P., theREE values decrease again and the average value drops to 163mug/g. Based on the characteristics of REE values, combined with the grain size parameters and Zr/Rb values etc, the evolution of paleoclimate in the Ili Basin and the westerlies since the Last Glaciation can be concluded as follows: From 80ka B.P. to 57ka B.P., the climate was warm and humid at first, but it became cold and dry gradually with strong fluctuation. It was warm and relatively humid during 57~28ka B.P. and became cold again from 28ka B.P. to 8 ka B.P. with a large increase of moisture. After that the Ili Basin has experienced a warm period with less precipitation.