Rapid industrialization and urbanization has been occurring in China since the introduction of the opening-up policy in 1978. The demands of building and infrastructure construction have increased rapidly, especially in the transportation and housing sectors in China. Large amounts of construction materials have been required in building construction and maintenance of the railway and road systems, especially steel and cement. Continued cement and steel production will require heavy raw material resource consumption and will emit a great deal of carbon dioxide (CO2). This study forecasts future steel and cement demand and related resource consumption and CO2 emissions for building and transportation infrastructure based on a material flow analysis of China. Furthermore, the effect of prolonging the lifetime of building and transportation infrastructure is appraised. The results indicate that building and transportation infrastructure will increase sharply through 2030. Although the demand for new construction will then decrease, steel and cement consumption will remain at a high level through 2050 because these are needed to maintain roads and railways. In addition, prolonging the lifetime of buildings and infrastructure is a useful way to avoid more raw material consumption and to mitigate CO2 emissions. However, its main effect is to decrease the demolition of buildings and reduce material use for the maintenance of roads and railways. Currently not enough countermeasures have been implemented to realize a low carbon–dematerialization society in the building and transportation construction sector. Future comprehensive efforts should include the reuse of waste construction material and a reduction in raw material consumption intensity by applying technical innovations.