【英文摘要】The enclosed lake is a sensitive indicator of climate change, and the mountain lake is at anatural state with relatively less influence by the human activities, thus it can reflect the climate situation authentically.Based on the satellite remote sensing materials and the meteorological data around the lakes, the changes in the water levels of the plateau enclosed lakes are analyzed in this study. It is found that water levels of Selin Co, Namtso present a distinct expanding trend in the past 40 years in north Tibet. Moreover, Selin Co expands at a rate of 20%, with an average of 420 km2/10a, thus it has become the largest salty inland lake during the period 1999-2008.That is closely related to the warming and humidified climate change in the recent years such as rise of the air temperature,increase of the precipitation, decrease of the evaporation rate and permafrost degradation. However, for the rainfall as the mainly supply of lakes, such as Yamzho Yumco and Mapangyong lake is shrinking slowly in past 30 years in middle and west Tibet.Because the lake's evaporation effect due to increasing temperature exceeded the effect in water level rise by increasing precipitation.