Non-oxidative aromatization of methane was carried out over Mo/CuH-ZSM-5 and compared with that over Mo/H-ZSM-5. Cu(II) ions act as promoter in this reaction and improve the activity of the Mo/H-ZSM-5 catalyst notably. The effect of Cu species on the chemical state of Mo species and the changes of Cu species itself after reaction were studied by ESR and XPS methods. The introduction of Cu ions by ion-exchange method altered the reduction of Mo species, suppressed the dealumination of ZSM-5 framework and decreased coke formation over the catalyst. The results showed improved catalytic performance of Mo/H-ZSM-5 catalyst. The amount and nature of the coke which were influenced by the introduction of Cu ions were also investigated.