The time and level of carbon emission peak will affect the development space of regions and have a far-reaching impact on the coordinated development in the Yangtze River Economic Zone (YREZ). This is also a problem to which we need to attach great importance when coping with climate change and regional management. Night-time light has become a typical remote sensing data used to describe the intensity of economic activities. This paper builds the measurement model of night-time light and GDP in the YREZ. According to the estimated results, the fitting precision is high and the GDP can be well explained by the night-time light by the model. This paper estimates and calibrates the GDP in the YREZ with the data of global nighttime light from 1995 to 2013, and then predicts the GDP in the YREZ from 2014 to 2050 under the situation of steady economic growth. Three simulation scenarios based on decay rate of carbon intensity are designed to explore the time and level of carbon peak in the YREZ. The result shows that there is no carbon peak in Jiangsu and Jiangxi with the same drop index of carbon intensity as in the12th Five-Year Planperiod, and carbon peak in other regions will appear before 2050. Furthermore, Yunnan will reach the carbon peak in 2025 which is 6.54*10~7 t. In addition, in the scenario of the drop index of carbon intensity as same as in the13th Five-Year Planperiod there is no carbon peak in Jiangsu, and the carbon peak in Anhui and Jiangxi will appear after 2040. In the same scenario, the carbon peak in Chongqing, Sichuan and Guizhou will appear around 2031. Furthermore, Yunnan will reach the carbon peak in 2023. In addition, the above two simulated scenarios both show that the time of carbon emissions peak in upstream area of Yangtze River is earlier than that in the midstream area. It should be pointed out that the decay rate of carbon intensity in Chongqing and Sichuan region reaches 4.30% and that in Guizhou and Yunnan region reaches 3.90%. Moreover, the carbon peak in Chongqing, Sichuan, Guizhou and Yunnan are 8.17*10~7, 1.36*10~8, 1.16*10~8 and 6.32*10~7 t, respectively. Therefore, the speed of economic growth is an important factor that affects the carbon peak. In the scenario with the goal of achieving carbon peak in 2030 in the YREZ, there are significant regional differences in the decay rate of carbon intensity. For example, the decay rate of carbon intensity in Yunnan is 2.58% and in Jiangxi is 7.53%. Therefore, regional imbalance in economic development should be taken into full consideration as well as the coordination of carbon intensity and economic growth rate when it comes to formulate carbon reduction plan. Meanwhile, emission reduction policy of achieving carbon peak by regions and by phases should be formulated, which is conducive to the target of achieving carbon peak with steady economic growth.