 This study examined the effects of five key factors on carbon dioxide, CO2, emissions in the Yangtze River Delta region between 2000 and 2019. It found that economic output had the greatest influence on CO2 emissions, followed by population size. Additionally, energy intensity had the strongest negative effect on CO2 emissions, while energy structure and industrial structure had minimal effects. Based on these findings, the authors suggested several policies to reduce CO2 emissions in the Yangtze River Delta region, including increasing energy efficiency, improving energy structure, and encouraging renewable energy sources. This article was offered by Yu Yuan and Sun Hsuk.