TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Catalyst: The X-ray (Lalpha ray) intensity of ruthenium in the catalyst is detected by performing line-analysis measurement of the catalyst about ruthenium one-way by electron probe micro analyzer (EPMA), so that the line passes along the center of the catalyst. The intensity of ruthenium detected between the distance from catalyst outer surface to r0/4 is 80% or more, where r0 is the distance from the catalyst outer surface to the catalytic center. The ruthenium dispersion degree is 30% or more. The starting material of potassium oxide is potassium hydroxide. Preferred Method: Hydrogen is manufactured at a reaction temperature of 400-800degreesC, reaction pressure of 0-0.5 MPa-G and molar ratio of water and carbon of 2.5-5.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Catalyst: The X-ray (Lalpha ray) intensity of ruthenium in the catalyst is detected by performing line-analysis measurement of the catalyst about ruthenium one-way by electron probe micro analyzer (EPMA), so that the line passes along the center of the catalyst. The intensity of ruthenium detected between the distance from catalyst outer surface to r0/4 is 80% or more, where r0 is the distance from the catalyst outer surface to the catalytic center. The ruthenium dispersion degree is 30% or more. The starting material of potassium oxide is potassium hydroxide. Preferred Method: Hydrogen is manufactured at a reaction temperature of 400-800degreesC, reaction pressure of 0-0.5 MPa-G and molar ratio of water and carbon of 2.5-5. SPECIFIC COMPOUNDS - The alkali-metal oxide (b) is potassium oxide.    EXAMPLE - Alumina (in g) (38.8) and kaolin powder (11.2) were mixed, molded and baked, to obtain an alumina-kaolin complex oxide of specific surface area 146 m2/g and pore volume 0.39 ml/g. Potassium nitrate (6.54) dissolved in ion exchange water (13.3), was added to the obtained alumina-kaolin complex oxide (35). Stirring was performed, followed by drying and baking, to obtain alumina-kaolin-potassium-oxide complex oxide of specific surface area 132 m2/g and pore volume 0.34 ml/g. Ruthenium trichloride hydrate (1.81) of ruthenium content 39 mass% dissolved in water (10.6), was added to the aqueous solution of alumina-kaolin-potassium-oxide complex oxide (30). Aging was performed for 1 hour, followed by pelletization, drying, washing and drying, to obtain a catalyst. The obtained catalyst contained ruthenium (2.3 mass%), potassium oxide (3.3 mass%), remaining kaolin and alumina. Using the obtained catalyst, manufacture of hydrogen was performed efficiently using desulfurized kerosene, at a reaction temperature of 450degreesC, reaction pressure of 0.005 MPa-G and molar ratio of water and carbon of 3.5.