Abstract: Using the Life Cycle Assessment, this paper conducts a quantitative analysis of electric vehicles promoted in Beijing including electric taxis, electric buses, and electric sanitation trucks as well as rental electric vehicles. Based on this research, this paper forecasts the effect of electric vehicles' energy conservation and emission reduction during the "13th Five-Year Plan" and provides some policy measurements in the industry. It concludes that:there is a positive energy conservation and emission reduction effect in the promotion of electric taxis, electric buses, electric sanitation trucks as well as rental electric vehicles in Beijing; power energy structure and fuel type etc., play a significant role in electric vehicle's emission reduction effect; the promoted new energy electric vehicles will save 154 hundred million kWh of electricity and reduce 39.4 million tons of CO2 by 2020.