Abstract: At present, pollution emissions both from the domestic development trend and from the international effect have become the focus of all sectors of society, and China's emission reduction task is still a long way to go. The key of effective emission reduction is to identify the factors that cause the increase of pollution emission, so as to find out the optimal emission reduction path and realize the purpose of emission reduction. Based on this, this paper compiled the environmental input-output table, constructed the corresponding environmental input-output model, and carried out structural decomposition (SDA) on it, so as to further explore the impact of three factors of pollution emission coefficient (emission reduction technology), production technology and the change of final demand on the emission of seven kinds of air pollutants. The analysis results showed that the entire increase in China's emissions, including reducing emissions of pollutants discharge coefficient changes, changes in final demand increase emissions of pollutants, the production technology changes is a small pollutant emission. Production technical change effects are much smaller than other two kinds of effects. Therefore, the change of emission coefficient (emission reduction technology) is the main path of emission reduction.