Carbon dioxide (CO2) activation and then hydrogenation is an alternative route to achieve the efficient control of CO2 emission. For activation, the neutral CO, molecule is first chemisorbed as carboxylate (CO2 delta-) or carbonate (CO32-) on catalysts, which is an important step. Up to now, the relationship elucidation between CO2 chemisorption states and hydrogenation activity still lacks of direct experimental evidence. Herein, the model Zn-Cr mixed oxide catalysts were created to fulfill the goal. The chemisorption states and hydrogenation mechanism were carefully identified by in situ DRIFTS experiments. Furthermore, additional characterizations demonstrated that CO2 chemisorption states depended on surface oxygen concentration and species. Combined with the results of CO2 hydrogenation experiments, the conclusion that chemisorption state as carboxylate was beneficial for higher hydrogenation activity was concluded.