The analyses of mineral assemblages of the core KS-2006 from Lake Kusai in the Hoh Xil area indicate that the carbon-ates in the sediments of Lake Kusai are mostly authigenic and mainly composed of aragonite.The variation of aragonite content probably reflects the temperature of lake water.Salt minerals were found since 2150 cal aBP, which is an indicative of the increase of salinity of lake water.Meanwhile, the increase of quartz content may be related to the enhancement of wind activity which is caused by the cold-dry climate in this area.The process of climatic and environmental evolutions of late Holocene in this area could be divided into 3 stages as follows:the climate was generally warm between 3770 cal aBP and 2550 cal aBP, then the temperature dropped slowly during 2550-2150 cal aBP;from 2150 cal aBP to present, the climate became cold and dry characterized by low temperature and high salinity of lake water, and strengthening of wind activity;however, there is a distinctly warm period occurred during 900-700 cal aBP.