Abstract: The water conservancy industry is promoting digital twins in an unprecedented situation. The basis of smart water management is urgently needed to solve the problem that three-dimensional visualization of water conservancy projects cannot meet the requirements of professional visualization software. In this paper, a three-dimensional visualization platform for water conservancy is built based on technologies such as Cesium, Vue and Springboot. This platform has realized the key application technologies of thematic three-dimensional visualization such as multi-source data fusion, flood discharge and flood evolution, and laid a foundation for later digital twin visualization.