Co/Sr-hydroxyapatite catalyst (Co/Sr-10(PO4)(6)(OH)(2): Co/Sr-P) shows high activity and low carbon formation on ethanol steam reforming. H-2-TPR measurements revealed that the Co species supported on Co/Sr-P was reduced only slightly more than that on typical Co/alpha-Al2O3. XAFS measurements revealed that Co2+ species was observed mainly on the Co/Sr-P catalyst after H-2-reduction at reaction temperature of 823 K. Co2+, i.e. CoO particle, on Co/Sr-P catalyst plays an important role as an active site for ethanol steam reforming with high coke resistance.