In this study,the spatial and temporal changes of future extreme temperature over northwestern China was evaluated using 11 regional climate models in the context of the Coordinated Regional Climate Downscaling Experiment for East Asia (CORDEX-EA) project.The main findings are as follows:1) The regional climate models could reproduce the spatial distribution of extreme temperature over northwestern China.2) The multi-model ensembles indicate that the FD and ID will decrease,while the TR and SU will increase in the 21st century over northwestern China.3) The WSDI and GSL of northwestern China show increasing trend,while the CSDI and DTR show decreasing trend in the 21st century.4) Due to the increase of temperature,TX90p and TN90p will increase,while TX10p and TN10p will decrease in the future.5) TXx,TNx,TXn and TNn show an increasing trend in the 21st century.Therefore,in the future,the probability of cold extreme events will decrease,and the probability of warm extreme events will increase,along with distinct spatial heterogeneity.