CO2 fixation by hydrogenation over coprecipitated 36 wt.% Co/Al2O3 has been studied under a range of reaction conditions to clarify the effects of reaction variables and to determine the kinetics and mechanism of the reaction. A comparison of the results with those reported for CO hydrogenation on the same catalyst indicates that, although product distributions of CO2 and CO hydrogenation differ, the kinetics and mechanism are similar.