By adopting the accounting method of CO2 emissions in Guidelines for the Preparation of Greenhouse Gas Inventories (Trial Version) in Cities and Counties (Districts) Issued by Guangdong Province, and based on the measurement results of the energy consumption and CO2 emissions in 9 cities in the Pearl River Delta Urban Agglomeration from 2010 to 2019, the decoupling coefficient and status of individual city from 2011 to 2019 can be obtained by using the“decoupling”elasticity of GDP and CO2 emission growth. Combined with the CO2 emissions and decoupling indices in recent 10 years, a discrimination method has been proposed of CO2 emissions peak of Pearl River Delta Urban Agglomeration, followed by an ultimate evaluation of the emissions peak situation in the nine cities. The results show that, in terms of total CO2 emissions, Guangzhou, Shenzhen, Zhongshan show a downward trend ona whole, while Foshan, Huizhou, Dongguan, Zhuhai, Jiangmen, Zhaoqing keep showing an upward trend；in terms of CO2 emissions intensity, Shenzhen is basically the lowest, to be followed by Zhuhai and Guangzhou；Zhongshan, Dongguan and Jiangmen are generally in a declining trend, Foshan, Huizhou, Zhaoqing are characterized with a fluctuation of declining then rising volatility. In terms of decoupling situation, Zhongshan shows a strong decoupling trend；Huizhou, Zhuhai, Zhaoqing are expansively connected；while Guangzhou, Shenzhen, Foshan, Dongguan, Jiangmen are weakly decoupled. In terms of CO2 emissions peak, accompanied by the current coordinated development of industrial structure and economic environment, Zhongshan, Guangzhou, Shenzhen, Dongguan, Jiangmen have been in the peak state, while Foshan, Huizhou, Zhuhai, Zhaoqing have not yet reached the peak.