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Objective：The changes of lake level on the Tibetan Plateau are important indicators for the study of climate and ecological environment changes. In-situ gauges can measure high precision lake level data, but are expensive to maintain and challenging to operate in remote areas. Satellite radar altimetry has now been used successfully for more than two decades to measure lake levels as an addition to gauge measurement. With the increase of Cryosat-2 observation data and the improvement of data processing technology, it is possible to effectively monitor the water level changes of more lakes. Method: This study presents a high-precise extraction method of lake level time series based on noise removal, improved empirical retracker (ImpMWaPP) and error mixture model. The Cryosat-2 SARIn data was used to obtain water level time series of 133 Tibetan Plateau Lakes from 2010 to 2018, and the spatio-temporal variations of these lake levels were analyzed. The accuracy of lake level extraction was validated using in-situ measurements and Hydroweb water level products. Results: In general, the lake levels on the Tibetan Plateau continue to rise, but the rate of increase is slower than that 2003-2009, with an average annual rate of change of 0.159 m/y. From the geographical distribution, the lake levels in the northern plateau rise most significantly, while the lake levels in the southern plateau tend to be stable. From the time, the water levels of most lakes showed a rapid rise in 2010-2012 and 2016-2018, while the water levels were relatively stable or slightly decreased at other times. Conclusion: This result showed the accuracy of lake level extraction in this study was higher than that of previous studies, and the change of lake levels on the Tibetan Plateau was similar with the previous studies. In the future work, the change of lake levels on the Tibetan Plateau will be further estimated using multi-altimeter data, and we will combine with the information of lake extent and study the change of lake volume to support the exploration of climate and environmental changes on the Tibetan Plateau.