NOVELTY - A hydrogen-producing system comprises hydrogen-producing material container (1) which accommodates hydrogen-producing material (10) which generates hydrogen by reaction with water, water container (4) which accommodates water and supplies water in hydrogen-producing material container, hydrogen production inhibitor container (3) which accommodates hydrogen production inhibitor which can inhibit hydrogen-producing reaction of hydrogen-producing material and water, and acceleration detection part (13) which detects acceleration a which acts on hydrogen-producing material container.    USE - A hydrogen-producing system used for fuel cell system (claimed).    ADVANTAGE - The hydrogen-producing system is excellent in safety, and has high reliability.    DETAILED DESCRIPTION - A hydrogen-producing system comprises hydrogen-producing material container (1) which accommodates hydrogen-producing material (10) which generates hydrogen by reaction with water, water container (4) which accommodates water and supplies water in hydrogen-producing material container, hydrogen production inhibitor container (3) which accommodates hydrogen production inhibitor which can inhibit hydrogen-producing reaction of hydrogen-producing material and water, and acceleration detection part (13) which detects acceleration a which acts on hydrogen-producing material container. The hydrogen production is suppressed when acceleration a which acts on hydrogen-producing material container is greater than or equal to a1 in which a1 is threshold value set beforehand by supplying hydrogen production inhibitor in hydrogen production inhibitor container to hydrogen-producing material container.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic block diagram of hydrogen-producing system. (Drawing includes non-English language text).    Hydrogen-producing material container (1)    Hydrogen production inhibitor container (3)    Water container (4)    Hydrogen-producing material (10)    Acceleration detection part (13)