A lot of studies have shown that the main reason for global climate change is the sharp increase in greenhouse gases emissions,especially carbon dioxide emissions caused by human activities. Wuhan City is in an accelerating stage of industrialization and urbanization,the energy consumption and carbon dioxide emissions will grow rapidly for a long time. In order to set a carbon emission reduction target,provide the scientific basis for promoting low-carbon city,this study used a method of scenario analysis to quantify the potential of reducing carbon emissions in the aspect of industry,transportation and construction industry. The carbon emission of the city was forecasted by analyzing the current carbon emissions,and the GDP growth in different carbon emissions reductions. Results showed that if the rapid growth of GDP will still rely on fossil energy consumption in the coming decades,it is difficult to decouple GDP growth and carbon emissions even if in the strengthening carbon emission reduction plan,only when GDP keeps an appropriate growing rate,which goes down to 10% in 2020,8% in 2030,6.5% in 2040,5% in 2050,the carbon emissions will reach the inflection points for optimum plan in 2040 and for strengthening plan in 2030 respectively. It also proposed a series of strategic and political suggestions which aim at the research results in the relationship between carbon emissions and city developing.