In this study, emissions released from a wastewater treatment plant in Istanbul, were estimated utilising air quality dispersion model. The treatment plant is located to the west of a residential site. So, the emissions have potential to affect the living people in the residential area. Emission factor and wastewater treatment capacity were used to calculate the emission rate. Turkish State Meteorological Service data were used in order to produce meteorological input to the model. Elevation data were gathered from Shuttle Radar Topography Mission data. AERMOD was executed with those input data. Hourly maximum, daily maximum, monthly maximum, and annual average concentration distribution plots were generated. The maximum values were 471, 171, and 42 mu g/m(3), on hourly, daily, and monthly basis, respectively. The maximum concentration observed on the annual average map was 29 mu g/m(3).