Hydrocarbon can be gasified with steam into fuel gas, including CO, CO 2 , H 2 , CH 4 , etc. For H 2 production, it is necessary to separate the other gases from hydrogen. In this study, hydrogen production by removal of carbon oxides during hydrocarbon gasification with CaO and other metal oxides was examined theoretically and experimentally.It was experimentally confirmed that when the hydrocarbon, water, and Ca(OH) 2 were set in a micro-autoclave at a temperature of 973K and a pressure of 25MPa, the only gas products were hydrogen along with a small amount of methane. CO was converted to CO 2 , and CO 2 was absorbed by Ca(OH) 2 to form CaCO 3 completely. CaOSiO 2 can absorb CO 2 to form CaCO 3 under the same experimental conditions. Others such as MgO, SnO, and Fe 2 O 3 were found to be unsuitable sorbents for CO 2 absorption in the gasifier at high temperature.By calcination, CaCO 3 can reform to CaO. Because the chemical energy contained in CaO can be released during hydrocarbon gasification, H 2 production efficiency as high as 70–80% can be expected.