The Mo3O/CCA was prepared by impregnation method using the (NH4)6Mo7O24·4H2O as the molybdenum source, carbon covered γ-Al2O3 (CCA) as support, and n-hexane as the carbon source. After carbonization of Mo3O/CCA obtained Mo2C/CCA. The catalysts prepared at different carbonization temperature were characterized by XRD. The effects of preparation and reaction conditions on dehydrogenation activity of the catalyst were studied in a fixed-bed down-flow reactor. The results show that the conversion of cyclohexane up to 91% was attained under the optimum condition as follows: CCA carbon covered 7.82%, final carbonization temperature 650 ℃, reaction temperature 475 ℃, reaction pressure 0.1 MPa, liquid hourly space velocity 2 h-1 and volume ratio of hydrogen to cyclohexane 200∶1.