Ceria (CeO2) with different crystal-planes were used as supports to synthesize gold (Au)/CeO2 catalysts for the preferential oxidation of carbon monoxide (CO). A CeO2 morphology-dependent Au-CeO2 interaction was observed. Au/CeO2-R in this present work performed the outstanding activity at lower temperature than ever since other works were reported. The Au catalyst supported on rod-shaped CeO2 exhibited the highest CO conversion level of 97.9% at 30 degrees C, followed by that on polyhedral-(94.0%), cube-(74.0%) and octahedral-(27.7%) shaped CeO2. The catalytic activities were strongly affected by the CeO2 crystal-planes and Au active species. The rod-shaped CeO2 enclosed by (110) and (100) planes might interact strongly with Au species, generating the most accessible active sites to absorb/desorb and activate the CO and oxygen molecules. The octahedral- shaped CeO2 enclosed by the (111) plane had the lowest catalytic activity since the (111) plane is the most stable and irreducible of the CeO2 (111), (100) and (110) planes, accounting for its decreased catalytic activity.