The Smart City, coordinated development of economy, ecology and society, is the future of cities. Urban renewal is an important way to build the Smart City. Based on the Smart City theory, the authors propose the “12345” model of urban renewal, which means developing a tailored proposal of the city and citizen, and building “one city management system, two supporting safeguard measures, three information infrastructure platforms, four urban management modes, and five application service systems.” The city will gain the ability of self-adjustment and self-improvement. Smart urban renewal model not only solves the problems of the city at this stage, but also promotes the all-round development of the city, and access to sustainable development.