The　Au/Fe2O3　catalyst　was　prepared　by　the　microemulsion　method　in　two　inverse　microemulsions,　Triton　X-100/n-hexanol/cyclohexane/(　aqueous　metal　salt　solution)　and　cetyttrimethylammonium　bromide　(CTAB)/n-hexano/(aqueous　metal　salt　solution),　respectively.　Ternary　phase　diagrams　of　the　two　systems　were　first　determined　to　get　the　inverse　microemulsion　area.　According　to　the　phase　diagrams,　surfactant,　oil　and　aqueous　solution　of　HAuCl4　and　Fe(NO3)(3)　were　mixed　to　form　a　homogeneous　microemulsion.　Then　the　Au/Fe2O3　catalyst　was　prepared　by　mixing　the　microemulsion　and　ammonia　solution.　The　effects　of　synthesis　parameters,　such　as　water　to　surfactant　mass　ratio　(r(w)),　surfactant　concentration　(　W),　surfactant　type,　calcination　temperature　and　gold　loading,　on　the　activity　of　Au/Fe2O3　for　the　water-gas　shift　reaction　were　investigated.　The　results　show　that　all　the　synthesis　parameters　have　remarkable　effects　on　the　catalyst　activity.　The　catalyst　sample　calcined　at　250　degreesC　has　the　highest　activity　and　the　activity　decreases　with　increasing　rw　and　W.　The　sample　prepared　by　the　microemulsion　consisting　of　nonionic　surfactant　(Triton　X-100)　shows　a　higher　activity　than　that　from　cationic　surfactant　(CTAB).　CO　conversion　reaches　99.5%　at　gold　loading　of　3%　and　200　degreesC.