This study has proposed a new solution concerning fuel consumption in China's transport sector, which has provided a more accurate basis for estimating CO2 emissions in the transport sector both on national and regional level. Our analysis indicated that CO2 emissions in China's transport sector in 2007 reached to 436Mt, higher than 408Mt estimated by IEA. The CO2 emissions in transport sector accounted for 7% of China's total fossil fuel combustion CO2 emissions, which is much lower than the global average level of 23%. The CO2 emission from road transportation was 376.6Mt, 37% higher than IEA's estimation. Therefore we thought IEA significantly underestimated the amount of CO2 emissions from road transportation in China, inevitably they overestimated CO2 emissions in other transportation means. The IEA's result of road transportation CO2 emissions is only 67.64% in the entire transport sector, but our study showed this ratio could be up to 86.32%. This study also preliminarily analyzed the driving‐forces of CO2 emissions in transport sector at regional level. The results showed that the CO2 emissions in transport sector are closely associated with GDP. Finally the article had reviewed some policies in China's transport sector.