In 2009 Chinese government committed to reduce 40–45% of CO2 emissions per GDP unit in 2020 compared to 2005.This paper compares CO2 emission intensity and constitution of China with other major countries, and combining with Chinese CO2 emission situation in 1980“2008 vertically analyses emission changes and present situation of China. This paper focus on using the equation of IPAT, to determine the threshold of CO2 emission increase, calculate GDP and CO2 emissions and analyzes the feasibility of the commitment about Carbon reduction target of China.