Atmospheric pollution is caused by sources due to human activities, such as: industrial facilities, energy production, agriculture, transport of any type and other human activities contributing directly or indirectly to the level of pollution; natural sources, such as: forest fires, volcanic eruptions and natural gas emissions are factors leading to this phenomenon. Referring to the transport sector, it should be noted that road transport has undergone an evolution in recent decades in the sense of the numerical increase of the motor vehicle fleet as well as the application of active and passive technologies with a qualitative effect and aimed at reducing emissions and fuel consumption, increasing their safety in operation. In this paper, the problem of the behavior of vehicles with depollution systems in traffic conditions is raised and their emissions are analyzed depending on its conditions, two models of commercial vehicles (Euro 6) equipped with a spark ignition engine (SIE) and a compression ignition engine (CIE) will be studied. The tests were carried out in a specially equipped laboratory (on a dynamometric stand). The speed/time parameters were recorded in real dynamic mode with a vehicle in order to later configure an urban driving cycle necessary for the laboratory tests. The diagrams made on the basis of the experimental data, in this paper, will present especially the polluting emissions for the two types of vehicles. An analysis will be made between the real urban driving regimes and the Low phase of the WLTP (Worldwide Harmonized Test Procedure for passenger cars and light commercial vehicles) to highlight the emission values ​​as clearly as possible. At the end of this paper, conclusions will be presented regarding the use of driving cycles for the evaluation of emissions in the urban area.