Transport sector significantly influences the decarbonization of the entire energy system. In this study, carbon tax scenario analyses with application of the TIMES model are carried out for China and USA to advance the understanding of the transport service demands, energy consumption, and CO2 emissions from a comparison perspective. Model results suggest that liquid fuels will keep dominating the transport energy consumption, while biofuels and electrification will facilitate the decarbonization of the transport sector both in China and USA. However, substantial differences exist between the two countries regarding the transport development pathways. FCEVs will be developed earlier and faster in USA and can fulfill 10% of the road passenger services in 2050 in USA, while less than 2% in China in TAX20 scenario; Carbon tax will raise the total energy system cost by 24% in China and 8% in USA in 2050 in TAX50 scenario and the additional cost of electricity in USA will be lower than that in China. It's also observed that the transport sector reacts to the carbon policy less and later than other sectors. (C) 2015 Elsevier Ltd. All rights reserved.