With the development of China, air pollutants are also growing rapidly in recent decades, especially in big cities of the country. To better understand the relationship between economic conditions and air pollutants in big cities, this study combined the carbon dioxide (CO₂) emissions of 17 provinces in China’s four key economic development zones (the Beijing-Tianjin-Hebei Region, the Bohai Economic Rim, the Pearl River Delta, and the Yangtze River Delta) for the first time and explored the decoupling of economic growth from CO₂ emissions. To achieve the research purpose, this paper constructs an economic benefit evaluation index system with employees, fixed investments, main energy productions as inputs, and gross domestic product (GDP) as output. In addition, the trend of economic efficiency changed from 2016 to 2020 was analyzed and compared by combining CO₂ emissions and set as undesirable output based on slacks-based measure (SBM) model and undesirable output model. The results show that from the perspective of provincial economic efficiency, the economic efficiency considering the undesirable output is lower than the traditional economic efficiency from 2016 to 2020. In terms of regional economic efficiency, the Bohai Economic Rim (BER) and the Beijing-Tianjin-Hebei Region (BTHR) are the most economically efficient of the four economic development zones (EDZs). Additionally, the mean value of regional green economic efficiency, in descending order, is the BER, the BTHR, the Pearl River Delta (PRD), and the Yangtze River Delta (YRD). In general, it is suggested that the government set different CO₂ emission reductiontargets for different areas in order to achieve rapid economic growth, taking into consideration the disparities in industrial structure and economic development levels of different EDZs.