The current study aims at modelling the dispersion of two pollutants, namely CO (carbon monoxide) and SO2 (sulfur dioxide) released from District 7 of Tehran Municiaplity, from 20 main line sources, by means of CALPUFF modeling system. CALPUFF is a non-steady state puff modeling software which employs meteorological, terrain, and land-use data to effectively simulate air pollutants' dispersion from a given source. CALMET software has been applied to provide meteorological conditions within the study domain. The study has been carried out on September 30, 2012 and shows that the modeled concentrations have been below both Iranian air ambient standard and NAAQS standard for CO and SO2. It also compares the measurements from the monitoring station of Setad Bohran, showing that the simulated hourly mean concentrations of the SO2 and CO do not follow similar temporal patterns for measurement values. For the absolute value, model results seem to be highly underestimated, compared to the monitored data (R2 = -0.41).