There are several gases that can pollute the air including nitrogen dioxide (NO2), sulfur dioxide (SO2) and carbon monoxide (CO). Nitrogen dioxide (NO2) is an ambient air pollutant along with nitrogen monoxide (NO) which is usually produced from human activities such as burning vehicle engine fuel, burning waste and burning coal and industry. On the highway in the Kalianak industrial area, Surabaya, various types of motorized vehicles pass through which cause pollution due to the burning of motorized vehicle fuel, especially in the morning. The most dominant pollutant gas arising from burning motor vehicle fuel is carbon monoxide (CO). The highest concentration of carbon monoxide in ambient air is at point 1, 19-08-2022 in the afternoon with a value of 14,652.09 µg/m3 and has the lowest concentration value at point 3 on 17-08-2022 in the morning of 3,125.98 µg/m3. The highest ambient air concentration of nitrogen oxides is located at point 1, 19-08-2022 in the afternoon with a value of 405.02 µg/m3 and has the lowest concentration value at point 3 on 17-08-2022 in the morning of 60.45 µg/m3. Keywords : Air Pollution, CO, NO, Modelling, Gaussian Plume, Dispersion