Abstract: Digital twin is a necessary technology for the smart upgrading and transformation of the water conservancy industry, and is also the key to build a digital twin basin of seven rivers. This paper has summarized various digital twin water-related technologies, stratified according to different purposes of technical means, and described the corresponding relationship between perception layer, facility layer, data processing layer, model layer, platform service layer, application layer and smart water conservancy. In order to build a smart water conservancy framework system with the functions of “multi data integration and visualization, operation situation awareness, comprehensive analysis and judgment, emergency linkage disposal”, a smart water conservancy dynamic modeling process was proposed by referring to the workshop dynamic modeling theory, based on real-time data perception, dynamic modeling and dynamic iteration of inverse model. Taking the digital twin project of a sluice in the river basin as an example, the six levels of smart water conservancy system were combined with the cutting-edge technology of digital twin. A model platform of related facilities was built to realize the purpose of monitoring sluice related data, quickly perceiving sluice security boundary and timely analyzing sluice operation situation. The relevant work is expected to provide a reference for promoting the construction of smart water conservancy and digital twin river basin.