The article presents a complex analysis of the impact of the technology of continuous casting of steel (CCS) on the rate of the air pollutant emissions from one of the Polish steel and iron plants. The emission sources occurring in the production process have been identified and their rate has been determined. The implementation of CCS has brought about significant changes in the production cycle of the steel plant and it also has caused an increase of the production effectiveness of steel products. The calculated environment effects have shown a considerable emission decrease of all pollutants in the scale of the whole steel plant.