This study has assimilative capacities of sulfur dioxide (SO2) and oxides of nitrogen (NOx) . AERMOD dispersion model was simulated to compute for ground level concentrations and spatial distributions of SO2 and nitrogen dioxide (NO2) within in Maptaphut industrial area. Emission input consisted of stacks which total amount of emission rate were used as baseline emissions. Maximum hourly average and annual concentrations predicted at 8 ambient air quality monitoring stations in the study domain were used to evaluate an assimilative capacity of these pollutants.. Emissions of SO2 and NOx were adjusted to the limit that predicted concentrations will not exceed their ambient air quality standards.