This article investigates the potentials of energy saving and greenhouse gases emission mitigation offered by implementation of building energy efficiency policies in China. An overview of existing literature regarding long-term energy-demand and carbon dioxide (CO2) emission forecast scenarios is presented. Energy consumption in buildings could be reduced by 100-300 million tons of oil equivalent (mtoe) in 2030 compared with the business-as-usual (BAU) scenario, which means that 600-700 million metric tons of CO2 emissions could be saved by implementing appropriate energy policies within an adapted institutional framework. The main energy-saving potentials in buildings can be achieved by improving a building's thermal performance and district heating system efficiency. The analyses also reveal that the energy interchange systems are effective especially in the early stage of penetration. Our analysis on the reviewed models suggests that more ambitious efficiency improvement policies in both supply- and demand-side as well as the carbon price should be taken into account in the policy scenarios to address drastic reduction of CO2 emission in the building sector to ensure climate security over the next decades. (C) 2008 Elsevier Ltd. All rights reserved.