Within the Institute of Environmental Protection – National Research Institute the Central Emission Database is being established. The Database will cover the most important emission sectors from anthropogenic activities, including usage of motor vehicles. The intensity of emissions of individual pollutants is the input data to air pollution dispersion models. Based on calculations performed by the air pollution dispersion models concentration of pollutants dispersed in atmospheric air (pollution immission) is provided. The annual average immision for a selected place in Poland is a measure of the threat to environment. In order to determine the intensity of pollutant emissions from motor vehicles it is necessary to recognize the intensity of vehicle motion and the volume of emission of pollutants depending on the type of vehicle motion. The task presented in this article is to determine the characteristics of pollutant emissions from motor vehicles depending on the type of their motion. The mean value of vehicle speeds was used to characterize the type of vehicle motion. The emission of pollutants from vehicles is therefore characterized by the dependence of road emissions of pollutants on the average speed of vehicles. The characteristics were determined for cumulated categories of motor vehicles: passenger cars, light commercial vehicles as well as heavy duty trucks and buses. The results of the inventory of pollutant emissions from motor vehicles in Poland in 2016 were used to determine the characteristics of pollutant emissions.