Effective control of peak carbon emissions plays a crucial role in the development of one region. Ac- cording to the statistical data of Hunan province during 2006-2015, different growth rates of per capita GDP and energy efficiency in Hunan province were simulated. Then, nine scenarios were designed to forecast the peak value of energy carbon emissions in Hunan province in the next 30 years. The research results show that the slower the energy efficiency grows and the earlier the peak value appears, the smaller the peak value is; the slower the growth rate of per capita GDP is, the earlier the peak value appears and the smaller the peak value is; when population is stable, the improvement of energy efficiency is one of the important factors leading to the peak value of the rapid growth of per capita GDP; in the high-high mode and medium-high mode, it cannot reach the peak value of carbon emissions before 2030 in Hunan province, and the per capita GDP growth exerts an great impact on carbon emissions. Compared with the impacts of 0.2% change for high, medium and low modes of per capita GDP, the 0.2% change for the three modes of energy efficiency have greater impacts on the prediction results. Therefore, to design the carbon emission reduction policies of carbon peak value, it is neces- sary to take carbon emissions space in Hunan province to prevent sharp economic fluctuation