Very recently, in the air pollution modeling the usual practice of neglecting the concentration correlation in the atmospheric photochemical reaction has been recognized as a source of serious error and it is shown that in the case of pure mixing (without chemical reaction) the concentration of air pollution decays in a natural manner but if the concentration selected is the chemical reactants, then the effect is that the transport of the air pollution is much more rapid (Kumar and Patel 1974, 1975; Patel 1974, 1976, 1983, 1984, 1992, 1998). Also the study of formation and destruction of photochemical smog is increasing at both small and large scales (Wanner et al., 1993). The prctical applications of the concentration fluctuations of reacting flow occure whenever the processes of turbulent flow and chemical reaction are merge, particularly when the reactant species are nonuniformly distributed. Urban air pollution is an interesting application of this problem because the pollutants are introduced in the atmosphere at various locations so that large concentration inhomogeneities exist before the pollutants are brought togather by movements and mixing large scale air masses by atmospheric turbulent winds. This case is common in the case of auto exhausts when the pollutants are discharged and subsequently mixed and react in the atmosphere. So, it is important to study the various aspects of the concentration correlation of urban air pollution with chemical reaction. A model of the transport of concentration correlation of urban air pollution with chemical reaction has been developed using the appropriate turbulent closue model. The result of this study, also shows that, in the case of pure mixing, the concentration decays in a natural manner, but if the concentraton selected id that of chemical reactant, then the effect is that the dispersion of concentration of air pollution is much more rapid.