The study was designed to investigate the catalytic hydrogenation of increasingly concerned CO2 to light olefins including ethylene, propylene and butylene, a series of critically important materials for various chemical syntheses, a win-win scenario for environment and economy. The Fe0.30Co0.15Zr0.30K0.10O1.63 catalyst, presented much poorer surface hydroxyl groups but richer oxygen vacancies (OVs) than the Fe0.60Co0.30K0.10O1.40, displayed light olefin space time yields (STY) of 4.93 mmol.g(cat)(-1).h(-1) at 310 degrees C and 2.0 MPa, which was 33.24% higher than the Fe0.60Co0.30K0.10O1.40 at the same reaction conditions. Extensive characterizations demonstrate that both oxygen vacancies (OVs) and surface hydroxyl groups (-OH) played important roles in the catalytic CO2 hydrogenation to light olefins, while OVs were more critical. OVs on the reduced Fe0.30Co0.15Zr0.45K0.10O1.63 were more active than those on the reduced Fe0.60Co0.30K0.10O1.40, which was very important to the enhancement of the oxygen storage, adsorption and activation of CO2 and thus the direct and efficient conversion of CO2 into CO, an important intermediate for the synthesis of light olefins synthesis. Thus, Fe0.30Co0.15Zr0.30K0.10O1.63 is a promising catalyst for converting CO2 hydrogenation to light olefins. (C) 2019 Elsevier Inc. All rights reserved.