NOVELTY - A hydrogen-producing apparatus (1) has a reaction container (2), an aqueous solution supply unit, a liquid feeding control unit, a discharge unit, an amount detecting unit of reaction residue, and a stop control unit. A reaction material is accommodated in the reaction container. The reaction material and aqueous solution are reacted in the reaction container, and hydrogen is produced. The aqueous solution supply unit supplies aqueous solution to the reaction container. The liquid feeding control unit controls circulation of aqueous solution.    USE - Hydrogen-producing apparatus is used for producing hydrogen for fuel cell installation (both claimed), hydrogen fueled engine, internal combustion engine, and electric power generating apparatus for motor vehicle and portable apparatus.    ADVANTAGE - The hydrogen-producing apparatus efficiently and stably produces hydrogen.    DETAILED DESCRIPTION - A hydrogen-producing apparatus has a reaction container, an aqueous solution supply unit, a liquid feeding control unit, a discharge unit, an amount detecting unit of reaction residue, and a stop control unit. A reaction material is accommodated in the reaction container. The reaction material and aqueous solution are reacted in the reaction container, and hydrogen is produced. The aqueous solution supply unit supplies aqueous solution to the reaction container. The liquid feeding control unit controls circulation of aqueous solution in the aqueous solution supply unit. The discharge unit discharges hydrogen produced in the reaction container. The amount detecting unit of reaction residue detects quantity of reaction residue in the reaction container. When the quantity of reaction residue detected by the amount detecting unit of reaction residue exceeds a predetermined amount, the stop control unit makes a halt condition to circulation of aqueous solution in the liquid feeding control unit.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the hydrogen-producing apparatus. (Drawing includes non-English language text)    Hydrogen-producing apparatus (1)    Reaction container (2)    Reaction unit (5)    Measurement unit (7)    Control unit (9)