Abstract: Air pollutants and carbon dioxide (CO₂) emissions reduction from motor vehicles play an important role in improving air quality and mitigating climate change. The data of vehicle population, road-driving conditions, meteorological, fuel composition and fuel consumption were comprehensively used to calculate the main air pollutants and CO₂ emissions of motor vehicles in Beijing based on COPERT Model. The emission characteristics, emission contribution of the vehicles of different types, and emission standard levels were identified. Urban-ADMS model was used to simulate and quantify the effect on surrounding environment by motor vehicles. The results showed that: the emissions of CO, NO_x, PM_2.5 and VOCs from motor vehicles of Beijing was 121 500, 40 600, 1 800 and 25 700 tons, respectively, in 2019. The structure of vehicles had been optimized. Vehicles with National IV and above standards accounted for 86.97%. Diesel passenger and freight vehicles accounting for 4% contributed greatly to the emissions, accounting for 84% and 60% of the total emissions of NO_x and PM_2.5, respectively. Evaporative emissions from gasoline vehicles accounted for 20% of VOCs emissions from motor vehicles, which required attention. Vehicle exhaust emissions contributed 15.7 μg/m³ to the average NO₂ concentration at five traffic monitoring stations which had a great impact on air quality. CO₂ emissions of motor vehicles were 16.83 million tons, of which diesel vehicle emissions contributed about 21%. Air pollutants and carbon emissions of motor vehicles need further coordinated control.