During the past years, one of the most important problems has been air pollution in urban areas. In this regard, ozone, as one of the major products of photochemical reactions, has great importance. The term "photochemical" is applied to a number of secohdary pollutants that appear as a result of sun-related reactions, ozone being the most important one. So far various models have been suggested to predict these pollutants. In this paper, we developed the model that has been introduced by Dabir, et al. [4]. In this model model than 48 chemical species and 114 chemical reactions are involved. The resluts of this development, showed good to excellent agreement across the region for coni pounds such as O3, NO, NO2, CO, and SO2 with regard to VOC and NMHC. The results of the simulation were compared with previous work [4] and the effects of increashlg the number of componets and reactions were evaluated. The results of the operator splitting method were compared witll non splitting solving method. The result showed that splitting method with one-tenth time step collapsed with non splitting method (Crank-Nicolson, under-relaxation.iteration method without splitting of the equation terms). Then we developed One dimensional model to 3-D and results were compared witll experimental data.