NOVELTY - A Bacillus subtilis sakane strain (FERM BP-10715) belonging to the genus B.subtilis and capable of producing hydrogen when agitated in the presence of water and iron (17), is new.    USE - For generating hydrogen (claimed).    ADVANTAGE - The new strain enables stable and economical production of highly purified hydrogen at a high-energy efficiency.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) a hydrogen generator (1) having a reaction liquor for hydrogen generation (12) containing the above-described novel strain and iron in an aqueous solution, an airtight container (11) for storing the reaction liquor for hydrogen generation, an agitation unit (13) for agitating the reaction liquor for hydrogen generation and a gas discharge pipe (14) which is airtightly connected to the airtight container and through which a hydrogen-containing gas (BB) generated from the reaction liquor for hydrogen generation is discharged from the airtight container, where hydrogen can be generated by agitating the reaction liquor for hydrogen generation with the agitation unit;    (2) method for generating hydrogen, involves preparing reaction liquor for hydrogen generation by adding iron to aqueous solution containing the above-mentioned strain, adding the reaction liquor to an airtight container, agitating the reaction liquor and generating hydrogen, and collecting the generated hydrogen gas; and    (3) battery comprising hydrogen generator comprising the above-mentioned reaction liquor for hydrogen generation in an airtight container, and anode and cathode electrodes immersed in the reaction liquor for hydrogen generation, or hydrogen generator comprising the above-mentioned reaction liquor for hydrogen generation in an airtight container, anode electrode connected with the gas discharge pipe for ejecting the gas containing hydrogen, fuel cell main body, cathode electrode and an air supply unit for supplying oxygen.    DESCRIPTION OF DRAWING(S) - The figure shows the block diagram of hydrogen generator and hydrogen isolation unit.    Hydrogen generator (1)    Reaction liquor for hydrogen generation (12)    Agitation unit (13)    Gas discharge pipe (14)    Hydrogen isolation unit (15)    Iron (17)    Hydrogen gas (BB)