The variations in the lake water storage in the Tianshan region are an important indicator of climate change and play a key role in understanding the hydrological mass balance. Based on altimetry and satellite gravity, we investigated the spatiotemporal characteristics of the lake water storage changes during 2002–2022, and examined the contributions and proportions of all of the hydrological components to the mass balance. The results indicate that the total water storage of the lake complex showed an increasing rate (0.73±0.10 Gt/a). We found two abrupt wet periods in 2010 and 2016 (the regional total mass increased by 65.73 Gt and 67.35 Gt, respectively), which were reflected not only by the lake water storage but also by the soil moisture, snow water, and even GNSS displacement fields. Compared with their contributions to the mass (22% and 14%), the variations in lake area were remarkably slight (0.01% and 0.014%). Among the hydrological components, the soil moisture played a dominant role, and the contribution of the snow accumulation changes was also considerable. The mass anomalies were closely related to the precipitation caused by the increase of water vapor content, which was further associated with the occurrence of ENSO events (r=0.55, p<0.01). The results revealed that the long-term trend of the GNSS vertical displacements exhibited a better stability after the load correction was applied, which could reflect the long-term ground deformation more accurately. This study contributes to our understanding of the complex hydrological and tectonic processes in the Tianshan region.