The carbon footprint of buildings relates to the energy system and building material production system from the perspective of life cycle. With the advancement of innovations in technology and energy conservation policies, emissions related to energy production and use as well as the production of building materials have been reducing in China. Consequently, this will influence the environmental performance of buildings indirectly. In this study, the life cycle carbon footprint of residential buildings in Beijing was calculated for the past 20 years, based on life cycle inventory databases in the context of energy and building materials, to determine the change in environmental performance of residential buildings. The results show that the carbon footprint in Beijing exhibited a decreasing trend, mainly as a result of carbon reduction in the energy mix and improvements in the building material production system. The carbon footprints of different structures also exhibited decreasing trends, although they varied in numbers. Considering life cycle stages, the use phase of buildings dominated the carbon footprint profile, which is mainly attributed to energy use. Although energy saving in the use phase was strongly correlated to the reduction of the carbon footprint of buildings, it had a limit in context of both economic cost and environmental cost. The coordination of various industrial sectors, such as energy production and material production industries should be paid sufficient attention while making policies for carbon reduction. Furthermore, as shown by the results, it is necessary to integrate the time parameter in life cycle assessment more efficient sustainable environmental management. The conclusions drawn from this study will be helpful for measuring the environmental performance in the policymaking of urban planning.