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Lanthanum-modified alumina supports prepared by the impregnation method have been used as supports for potassium-promoted iron catalysts in CO 2 hydrogenation. The catalysts have been characterized by X-ray diffraction, CO 2 chemisorption, temperature-programmed reduction (TPR) and temperature-programmed decarburization (TPDC) techniques. The selectivity towards total hydrocarbons and lower olefins (C 2 -C 4 ) was found to increase with increase in lanthanum content up to 4 wt% in Fe-K/La-Al 2 O 3 catalysts and to decrease above this lanthanum content. The TPR profiles of the catalysts of lanthanum-modified Al 2 O 3 shows the reduction of Fe 2 O 3 to iron(0) follows a threestage reduction mechanism through formation of the FeO phase. The TPDC profiles show the formation of three types of carbide species on the catalysts during the reaction. The activities of the catalysts are correlated with physico-chemical characteristics of the catalysts.