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Evapotranspiration is the highest outgoing flux in the hydrological cycle in Xinjiang, Northwest China. Quantifying the temporal and spatial patterns of future evapotranspiration is vital to appropriately manage water resources in water shortage drylands. In this study, the Common Land Model (CoLM) was used to estimate the regional evapotranspiration during the period 2021-2050, and its projected changes in response to climate change under two Representative Concentration Pathways (RCP) scenarios (i.e., RCP4.5 and RCP8.5) were analyzed using the Singular Value Decomposition (SVD) technique. The results indicated that the mean regional evapotranspiration was comparable under the two scenarios during 2021-2050, with a value of 127 (+/- 11.9) mm/year under the RCP4.5 scenario, and 124 (+/- 11.1) mm/year under the RCP8.5 scenario, respectively. Compared to the historical period of 1996-2005, the annual mean evapotranspiration during 2041-2050 will marginally decrease by 0.3 mm under the RCP4.5 scenario and by 0.4 mm under the RCP8.5 scenario, respectively. Empirical Orthogonal Function (EOF) analyses show that the evapotranspiration in relative high altitudes of Xinjiang present strong variations. The SVD analyses suggest that the changes in evapotranspiration are more closely linked to local precipitation variations than to temperature. The results would provide reliable suggestions to understand future changed in evapotranspiration and improve the regional strategy for water resource management in Xinjiang.