Density functional theory (DFT) calculations were carried out in the study of oxidation of benzene to phenol by N2O on relaxed [(SiH3)(4)AlO4M] (where M=Fe, Co) cluster models representing Fe- and Co-ZSM-5 surfaces. The catalytic cycle steps are completed for both Fe-ZSM-5 and Co-ZSM-5 clusters. The general trend of the results that were obtained in terms of activation barriers for the Fe-ZSM-5 cluster is in agreement with the experimental and theoretical literature. It was observed that the phenol formation step is the rate-limiting step for both clusters and Co-ZSM-5 surface has a lower activation barrier than the Fe-ZSM-5 surface (i.e. 35.82 kcal/mol vs. 45.59 kcal/mol, respectively).