Abstract: CO2 emissions from the transportation industry are one of the three major sources of carbon emissions in China, and the increase in CO2 concentration caused by highway construction activities has indirectly led to the enhancement of the greenhouse effect, climate warming and threats to human living space. Therefore, highway construction projects are the key emission reduction targets for China in the context of "double carbon" target. In this paper, an in-depth analysis of carbon emission inventories and carbon emission factor catalogs of domestic and foreign transportation industries is conducted, and the carbon emission factor data in line with the characteristics of China's transportation industry is extracted and summarized based on the existing estimation indexes of highway projects and the unit price calculation sheet of construction machinery and equipment in China's traditional transportation industry. Based on the Attribution Life-Cycle Assessment (ALCA) method, we adopt the "bottom-up" carbon emission measurement concept of highway projects and divide the project activities into sub-projects - divisional projects - unit projects, thereby establishing the carbon emission database and carbon emission measurement model during the construction period. Accordingly, an intelligent carbon emission measurement application for highway projects was built using MATLAB together with a carbon emission measurement analysis for a certain mileage of two sections of expressway branch. The analysis results show that the measurement application can effectively locate the carbon emission sources and the top carbon emitters during the construction period of highway projects, and provide data and theoretical basis for energy conservation and emission reduction in the transportation industry.