Co-BaCO3 catalysts exhibited high catalytic performance for oxidative dehydrogenation of ethane (ODE) using CO2 as oxidant. The maximal formation rate of C2H4 was 0.264 mmol center dot min(-1)center dot(g center dot cat.)(-1) (48.0% C2H6 conversion, 92.2% C2H4 selectivity, 44.3% C2H4 yield) on 7 wt% Co-BaCO3 catalyst at 650 degrees C and 6000 ml. (g center dot cat.)(-1) h(-1). Co-BaCO3 catalysts were comparatively characterized by XRF, N-2 isotherm adsorption-desorption, XRD, H-2-TPR and LRs. It was found that Co4+supercrip-O species were active sites on these catalysts in ODE with CO2. The redox cycle of Co-O species played an important role on the catalytic performance of Co-BaCO3 catalysts. On the other hand, the co-operation of BaCO3 and BaCoO3 was considered to be one of possible reasons for the high catalytic activity of these catalysts.