This paper describes current auto industry's advanced low-carbon technologies at home and abroad, including engine emission reduction technologies, efficient transmission and drive technologies, alternative energy technologies and electric energy-saving technologies. By comparing these technologies, we can discovery key low-carbon technologies of automobile needed to focus on. China's automotive technological accumulation is much less than advanced countries. Not only free technical competition between the domestic auto companies is demanded, joint development is also needed. Automobile enterprises should cooperate in innovation to improve the country's overall innovation in the automotive industry level.