Abstract: Based on Landsat satellite remote sensing data, the water body index and correlation analysis methods were used to analyze the water area change of Qixiangco lake in Shuanghu county of Naqu city from 1988 to 2018. The results showed that the water area of the lake increased significantly by 33.37 km² in the recent 31 years (R=0.88, P < 0.001) with a rate of 18.03%. In terms of space, the lake area expanded continuously around in the past 31 years, especially in the east, the west, and the north. In addition, the annual average temperature in the region where the lake is located increased, the evaporation capacity significantly reduced, and the frozen soil depth was also significantly reduced. Under the combined action of the above factors, the increase of lake water supply source and lake water volume lead to the continuous increase of lake area.