Lakes on the Tibetan Plateau are sensitive indicators of global climate change. In the last 55 years,the climate of the Hoh Xil region showed a significant warm and wet trend,in which the temperature rise rate was 0. 33 ℃·(10a)~(-1) (R = 0. 746,P < 0. 01) ,and the increasing rate of precipitation was 23. 4 mm·(10a)~(-1) (R = 0. 422,P < 0. 01) . Over the past 40 years,the area of salt lake has shown an increasing trend. Among them, the area of Salt Lake before dike burst increased by 1. 63 km~2· a~(-1) from 1976 to 2011,and after dike burst it continued to expand at the rate of 8. 51 km~2·a~(-1) . On the whole,in the past 40 years,the area of Salt Lake has experienced three stages: slowly increasing (1976-2011) sharply increasing (2012-2013) steadily increasing (2014-2017) . The main reason for the early expansion of the Salt Lake area was the warm and wet of the climate in the Hoh Xil region. The reason for the sharp increase in the area in the later period was due to the dike burst of the Zonag Lake in the upper branches of the Salt Lake on September 15,2011,resulting in three lakes downstream (Lake Kosei,Lake Dinard Noir) ,and Salt Lake are connected in a row; glacial and frozen water melting may be the cause of the expansion of the Hoh Xil Salt Lake area,but it is not the main reason. In the later period,the area of Saline Lake will also show a steady increase trend. The expansion of the Salt Lake area has led to the desalinization of Salt Lake,and the area where the surrounding grassland has been submerged and destroyed continues to expand. Which not only damages the ecological environment surrounding grassland,but may also have an adverse effects on major engineering facilities around Hoh Xil. In view of the fact that the area of Salt Lake will continue to increase in the future,it will adversely affect the major engineering facilities around it. Therefore,long-term and continuous tracking and observation of Salt Lake Lake using multi-source satellite data will remain the focus of relevant government departments.