Abstract: The urban lifeline safety engineering aims to prevent major safety accidents such as gas explosions, bridge collapses, road surface collapses, and urban waterlogging. Based on the public safety technology and combined with digital technologies such as the internet of things, big data, and cloud computing, it is aimed to achieve overall monitoring, dynamic examination, early warning, and efficient response of lifeline engineering. First, the theoretical system of urban lifeline safety engineering is elaborated, including comprehensive monitoring theory of urban lifeline safety, the platform framework of sensing, transmitting, knowing, and using, the risk prevention and control mechanism of multi⁃departmental collaborative linkage, and the standard system for urban lifeline monitoring and operation services. Second, the representative monitoring and early warning technologies in four typical fields, such as urban gas, bridge, water supply, and drainage, are analyzed. Third, the basic situations and application effectiveness of urban lifeline safety engineering construction in Hefei City and Anhui Province are introduced. Finally, the future development trends are proposed from three perspectives of national major needs, technological equipment innovation, and application scenario expansion. The research results can strengthen the understanding and recognition of urban lifeline safety engineering, and assist in the comprehensive promotion of urban lifeline safety engineering in China.