MnO is a desirable Promoter to Fe/Silicalite-2 catalyst for the production of light olefins from CO2 hydrogenation. With addition of MnOpromoter to Fe/Si-2 catalyst, the selectivity to lighy olefins, eslpecially theolefin/paraffin ratio. inereased obvionsly. while the yield of CH4 as well asCO formed from CO2 hydrogenation was hardly affected by MnO additionThe conversion of CO2 was insensitive to the addition of MnO promoter Ithas been exhibited that the CO adsorption ability and capacity inereasedwith MnO introduction which was favorable for the first formation of C2H4and C3H6 during Co2/CO hydrogenation and for the inerement of olefinselectivity by means of CO2-TPD CO2/H2-TPSR and CO/H2-TPSR as wellas CO2/H2 pulse reaction characterizations.