Abstract: The Qinghai-Tibet Plateau has the highest and most numerous group of plateau lakes in the world, the largest glacier area on earth except for the North and South poles, and the largest perennial permafrost distribution area in mid-latitude in the world. Grasping the changing characteristics and trends of water resources on the Qinghai-Tibet Plateau is crucial for the construction of the ecological security barrier on the Qinghai-Tibet Plateau. Based on the literatures, the structural characteristics, changes and problems of water resources on the Qinghai-Tibet Plateau are systematically sorted out and summarised. Over the past decades, the water resources of the Qinghai-Tibet Plateau have shown the characteristics of glacier retreat, snowpack reduction, lake expansion, increased runoff changes, wetland degradation, permafrost degradation, etc., and the overall trend of accelerated conversion of solid water resources to liquid water resources on the surface. This trend of conversion has led to the aggravation of water resources imbalance and increased the risk of water disasters, bringing new challenges to water resources security. There is a need to strengthen the monitoring of water resource changes on the Qinghai-Tibet Plateau, to carry out a systematic survey of the status and evolution of water resources on the Qinghai-Tibet Plateau, to improve the ability to comprehensively simulate the availability of water resources on the Qinghai-Tibet Plateau under different scenarios, and to systematically assess the imbalance and security of water resources on the Qinghai-Tibet Plateau.