This　paper　reports　a　study　on　the　influence　of　calcination　temperature　on　the　catalytic　behavior　of　the　Au/iron　oxide　systems　in　the　water-gas　shift　reaction.　The　catalytic　activity　has　been　found　to　be　strongly　dependent　on　the　catalyst　pretreatment,　decreasing　on　increasing　the　calcination　temperature.　Detailed　characterization　of　the　uncalcined　and　the　calcined　sample　at　different　temperatures,　employing　BET　analysis,　XRD,　H-2-TPR,　HRTEM　and　XPS,　has　shown　that　the　catalytic　behavior　is　related　to　the　gold　state　and/or　the　particle　size　and　the　properties　and　structure　of　iron　oxide　support.　Both　the　oxidation　state　and　dispersion　of　gold　and　the　phase　transition　and　its　crystallinity　and　reductive　property　of　the　support　exert　great　influence　on　the　catalytic　performance　of　the　gold/metal　oxide.　The　wave　of　the　activity　within　the　middle　reaction　temperature　range　(i.e.　523-623　K)　could　be　attributed　to　the　difference　of　the　operating　temperatures　belonging　to　the　gold　species　and　the　active　magnetite　phase.　(C)　2003　Elsevier　B.V.　All　rights　reserved.