Recently, the economy has grown rapidly in China's Central Plains urban agglomeration, with high energy consumption and a huge pressure on reducing CO2 emissions. Thus, low-carbon development is an important measure to solve economic, energy and environmental problems. To analyse low-emission development, this paper clarifies the evolutionary characteristics of CO2 emissions and the decoupling relationship between GDP and CO2 emissions based on the latest available data from 2000 to 2015. The results indicate that CO2 emissions of Pingdingshan and Changzhi are higher in the same year. The ratios from coal consumption accounting for the total CO2 emissions are clearly bigger than from other energy types and industrial processes. Changzhi, Luoyang and Pingdingshan have reached their peaks. Five cities have experienced strong decoupling after 2010, 13 cities present weak decoupling, 4 cities present growth connection, and 7 cities show growth negative decoupling. It can be concluded that a relatively smaller proportion of industry and strict policy implementations of coal reduction are the main factors in inhibiting the decoupling. So the proportion of coal purification should be increased firstly. Then, the energy consumption structure should be changed from the traditional coal consumption structure to coal, oil and gas. Lastly, economic means can be used to control CO2 emissions.