Most air pollution originates from combustion processes, so it is important to make quantitative as well as qualitative analysis, as the sources of pollution can be stochastic – especially for road traffic. The point of our study is to better determine road traffic as one of the largest pollution sources in the city of Niš, Serbia. The research was conducted at several locations in the city that represent all of the main roads across the city. Parameters considered in the study were traffic frequency, vehicle type, annual vehicle mileage in the city, and average vehicle velocity. Besides these parameters, roadside CO₂ concentration was measured for evaluation. These data were used as the input for the COPERT methodology of air pollutant emissions calculation from road transport. On the basis of these data, annual CO₂ emissions and major pollutants were calculated, as well as the specific average emissions on roads. According to this, a classification of roads in respect to their specific average emissivity is given at the end of this paper.