Aiming at the key problems of water conservancy project management and fl ood disaster prevention,thispaper puts forward a solution based on digital twin smart platform by studying and applying the technology of digitaltwin,in order to improve the management effi ciency of water conservancy project and the ability of fl ood disaster prevention. By establishing the digital twin model of Xiaoqing River Basin,the digital modeling and simulation of theactual engineering scene in this basin are realized. At the same time,the platform integrates the“ four pre” system forfl ood control,which can provide accurate fl ood forecasting and early warning information,and can eff ectively copewith fl ood disasters. The design and application of the digital twin smart platform in Xiaoqing River Basin providesimportant technical support and decision-making basis for fl ood disaster prevention and project implementation,whichis helpful to improve management effi ciency and reduce disaster losses.