Fe/ZSM-5 catalysts were prepared by three kinds of ion exchange methods: aqueous ion-exchange (AI), hydrothermal ion-exchange (HI) and solid-state ion-exchange (SI). Their catalytic activities were tested for NOx reduction by CO in a separated NOx adsorption-desorption process. In this paper, performances of adsorption, reduction and dynamic adsorption-reduction were all investigated. All three catalysts exhibited good reduction activity at above 300 °C. Fe/ZSM-5(SI) exhibited excellent NOx removal efficiency in the dynamic adsorption-reduction experiments. However, in the dynamic process the adsorption efficiency of Fe/ZSM-5(AI) and the reduction efficiency of Fe/ZSM-5(HI) is not very good. The catalysts were further characterized by SEM, BET, XRD, XRF, XPS and TPD. It was found that the Fe content of the Fe/ZSM-5(SI) was the highest. Further, Fe is supported in the form of Fe2O3 particles. Bronsted acid sites were also playing a major role in the high catalytic activity. TPD and in situ DRIFT experiments show that more Fe loading in α acid sites could result in a higher NOx removal efficiency.