Despite the large and growing role of exports in Korea’s carbon emissions, they have been largely overlooked in Korea’s carbon neutrality strategy. With this in mind, we analyze Korea’s aggregate emission intensity of exports (AEI_E), an indicator of the environmental efficiency of exports, which decreased from 1.37Kt/$M to 0.74Kt/$M during 2000–2014. Using the multi-regional input-output model and two-stage multiplicative structural decomposition analysis (MSDA), we uncover drivers of changes in the AEI_E. Analysis of bilateral AEI_E shows that exports to developed countries had a large impact on the decline while exports to developing countries have risen in importance. MSDA shows that the carbon intensity effect contributed most to the decline but that trade in intermediate goods and trade in final goods were also important. At the sectoral level, manufacturers of basic metals, electricity, gas, steam and air conditioning supply and transportation sectors were shown to be important drivers of the decline in the AEI_E. As the first study to analyze the drivers of Korea’s AEI_E, this paper suggests various abatement policies to help achieve the goal of carbon neutrality by 2050.