Abstract: The catalytic performances of monolithic catalyst Ru/Al2O3/Cordierite in selective hydrogenation of benzene to cyclohexene were examined in a circulated monolithic fix-bed reactor. The monolithic catalyst exhibited excellent performances in the selective hydrogenation of benzene to cyclohexene; a high cyclohexene yield of 18% was obtained. The addition of aqueous solution of ZnSO4 during reaction was important to obtain high cyclohexene selectivity. The results indicated that both the catalyst with high activity and selectivity and the intensification of external diffusion for cyclohexene were crucial to get high cyclohexene yield.