For the reduction of greenhouse gas emission in the transportation sector, various countermeasures against CO₂ emission have been taken. The eco-driving has been paid attention because of its immediate effect on the CO₂ reduction. Eco-driving is defined as a driving method with various driving techniques to save fuel economy. The eco-driving method has been promoted to the common drivers as well as the drivers of carriers. Additionally, there are many researches about improvement of fuel efficiency and CO₂ reduction. However, the eco-driving will have the reduction effect of CO₂ emission, the influence of the eco-driving on air pollutant emission such as NOx is not yet clear.In this study, the effect of the eco-driving on real-world emission has been analyzed using the diesel freight vehicle with the on-board measurement system. In the test, two drivers drove the one diesel freight vehicle in the same route; one driver drove the vehicle normally, and another one drove it with the early shift-up driving. The CO₂ reduction effect by the early shift-up driving was examined, as the same time, NOx emission behavior was compared between the driving with and without the early shift-up driving.As a result of the on-road driving test under the urban driving condition, the early shift-up driving had a sufficient effect on CO₂ reduction and fuel efficiency improvement. However, the early shift-up driving caused an increase of NOx emission. This result is largely concerned with the engine operating region, such as engine speed and engine torque.