“The optimal allocation and balanced development of water resources in the the Pearl River basin is the key to ensure regional sustainable development. Relevant experts have constructed an evaluation index system for spatial balance of water resources from four dimensions of water resources, society, economy and ecology. The the Pearl River basin is divided into four regions, namely Xijiang, Nanjiang, Beijiang and Dongjiang. Dagum Gini coefficient and obstacle degree model are used to analyze the spatial balance of water resources and its obstacle factors in the the Pearl River basin. The research results show that from 2017 to 2022, the spatial balance difference of water resources in the the Pearl River basin mainly comes from regional differences, and its multi-year average contribution rate is as high as 52.77%. Among them, the Xijiang region has serious surface water leakage due to the plateau and mountainous terrain, and the water resources development and utilization rate is less than 40%, while the Dongjiang River basin has complete water conservancy projects, with utilization rate of more than 80%, so it is necessary to focus on the coordinated allocation of regional water resources; From the perspective of dynamic change, the the Pearl River basin will be in a critical equilibrium state from 2017 to 2022, with Gini coefficient fluctuating in the range of 0.246~0.350; Obstacle factor analysis shows that water resources subsystem and social subsystem are the main obstacle factors to achieve spatial balance of water resources in the Pearl River basin provinces.”