Environmental regulations of trading partners will have an important impact on exports to Korea, which is highly dependent on foreign countries. In this study, the impact on exports by Korean company size (small and medium-sized enterprises, medium-sized enterprises, and large enterprises) was analyzed using the OECD's environmental policy stringency (EPS) as an environmental regulation variable. The analysis period is from 2009 to 2020, when export performance data by company size are available, and an empirical analysis was conducted on 33 countries where environmental policy stringency (EPS) was established. As a result of the analysis, as the environmental policy stringency (EPS) of the trading partner increased, exports of large companies and SMEs in Korea decreased. At this time, it was found that exports of large companies decreased more than that of SMEs, and in the case of mid-sized enterprises, it was not statistically significant. In literature studies, Korean companies respond that they are preparing countermeasures against climate change and carbon neutrality, but as a result of the empirical analysis, exports decrease in countries with high environmental policy stringency (EPS), so it seems that companies need more active countermeasures against environmental policies.