The ARDL-ECM model is constructed to test the long-term and short-term impacts of foreign direct investment (FDI) on carbon emissions in the national samples and samples from the eastern, central, and western regions. The results are as follows. (1) There are significant regional differences in the impact of FDI on China’s carbon emissions. The eastern region of China supports the “pollution paradise” hypothesis, while the other regions support the “pollution halo” hypothesis. (2) The longterm and short-term effects of FDI on carbon emissions are significantly different. (3) The scale effect of carbon dioxide emissions is significantly positive, while the technological progress effect and structural effect are significantly negative. In addition, the promotion effect of FDI on carbon emissions in eastern China mainly comes from the larger scale effect and the smaller technological progress effect. (4) FDI is the Granger cause of carbon dioxide emissions, and FDI has a causal relationship with GDP, technological progress, and industrial structure. Other variables affect carbon emissions through their interaction with FDI, which provides a practical basis for the decomposition of the carbon emission effect of FDI into scale effect, technological effect and structural effect.