A long time series of the Ayakekumu Lake level change has been compiled by combination of the T/P,RA-2 and Hydroweb data.In addition,we assessed changing index of the Ayakekumu Lake during 1995-2015 based on Landsat images.The results showed that,the Ayakekumu Lake area and level increased continuously during the observation period,the area of lake increased from 624 km~2 in 1995 to 995 km~2 in 2015,and water level increased by 5 m in total in the period of 1995- 2015.Meanwhile,the air temperature had risen,and the area of glaciers retreated from 361.27 km~2 in 1994 to 345.26 km~2 in 2016.We concluded that the water volume change was related with climate factors,and the main factor was warm-wet climate.Additionally,atmosphere warning led to water level increase due to glaciers melting.The water volume changing in Ayakekumu Lake could be affected by the increasing precipitation as well as dropping evaporation.Some factors are likely to affect lake expansion,including permafrost melting and precipitation at high altitudes.In sum,accurate measurements of lake ice and water levels are critical for understanding the water resource balance and hydrologic cycle in arid or semi-arid regions of China.