In view of the lack of applicable evaluation methods for the carbon emissions in asphalt surface construc- tion that results in the difficulty in constraining the carbon emission effectively，this paper investigates and detects the carbon emission of 13 asphalt pavements under construction in several areas in China，and establishes a formula to calculate the carbon emission due to the combustion of energy and the high-temperature decomposition of asphalt． Then，based on the carbon emission inventory，quantitative evaluation grading standards for carbon emission are put forward to establish an evaluation system，and the key process and measures of carbon reduction are determined by means of principal component analysis． The results show that the ratios of Grade Ⅰ (excellent)，Grade Ⅱ (good)，Grade Ⅲ (medium) and Grade Ⅳ (poor) are respectively 15%，31%，46% and 8%; and that the pivo- tal processes of carbon emission reduction include aggregate heating，asphalt heating and asphalt mixture rolling， and the carbon emission of the former two processes are mainly affected by the type of raw material’s heating ener- gy，while the carbon emission of asphalt mixture rolling is mainly affected by the type of asphalt．