The studies and legal policies carried out for the protection of air quality have become more critical with the increasing of environmental awareness today. Improving air quality with environmentally friendly regulations like promoting renewable energy use are now included in the country's policies. Evaluation of the current situation is of great importance in determining the policy for the improvement of air quality. In order to accurately determine the amount of emitted pollutants to the atmosphere and prepare clean air action plans for the cities, it is necessary to calculate the emission inventory of air pollutants according to their sources and to report the emissions emitted to the atmosphere at specific periods under the national and international responsibilities. Therefore, it is necessary to prepare the emission inventory in a particular order using information from sources of pollution and local emission factors. In this study, the Marmara Region was selected as the pilot region and the Development of National Emission Inventory project implemented for the first time in our country with the Ministry of Environment and Urbanization. The part for the point sources in this study is explained in this paper, and the results related to the metal industry are given. 128 emission sources of 27 plants were used in the calculation of the emission inventory of the metal sector in the Marmara Region. Emission values according to calculations made with national emission factors are as follows; 46,849 ton/year for CO, 7,589 ton/year for SO2, 8,906 ton/year for NOx, and 1,759 ton/year for TSP.