The fuel consumption in urban area and suburban,and the comprehensive fuel consumption of the target car were compared in the same experimental conditions and using different kinds of lubricating oils in NEDC test.The influence of lubricating oil properties on the vehicle fuel economy was analyzed.The experimental results show that in all NEDC test,the temperature of engine oils is between 25 ℃ and 100 ℃,among which the oil temperature is between 25 ℃ and 80 ℃ for urban condition,and between 80 ℃ and 100 ℃ for suburban condition.The low viscosity lubrication oil can effectively reduce the fuel consumption,but over low viscosity lubrication oil will increase the fuel consumption in suburban condition.Adding viscosity index improver and friction modifier can all effectively reduce fuel consumption.