This paper reports the result of CFD simulation of catalytic oxidation of benzene onmonolithic catalyst. The geometries ofthe catalyst and reactor were designed in Gambitsoftware and simulation of catalytic oxidation was carried out in fluent 6.2. Results ofsimulation showed excellent agreement with the experimental data. This studyconfirmed the accuracy of the used model in this simulation (Mars van Krevelen).Furthermore, CFD made it possible to obtain a more accurate view ofheat transfer andfluid flow. This study confirmed CFD is the best tool for study offluid regime and heattransfer and especially, concentration of species, and surface deposition along thereactor in the chemical process.