PROBLEM TO BE SOLVED: To provide a hydrogen addition device or the like capable of housing an article and filling the inside thereof with hydrogen gas.SOLUTION: A hydrogen addition device 40 includes a first container 31 with a bottom having a first opening 311 and a check valve 33 that is disposed nearer to the bottom than the first opening 311 and opens when the inside pressure is higher than a predetermined first pressure； a second container 32 with a bottom having a second opening 321 of a shape to engage with the first opening 311； and a hydrogen generator 20 that has a housing part for housing a hydrogen generator sheet containing magnesium hydride and a bag containing magnesium hydride and one or a plurality of open holes 21 through which the housing part communicates with the outside, and is arranged in a space between the first container 31 and the second container 32.SELECTED DRAWING: Figure 1【課題】物品を収容し、内部に水素ガスを充満させることが可能な水素添加装置等を提供すること。【解決手段】水素添加装置４０は、第１開口部３１１と、内部の圧力が所定の第１圧力よりも高い場合に開く前記第１開口部３１１よりも底に近い場所に配置された逆止弁３３とを有する有底の第１容器３１と、前記第１開口部３１１に対応する形状の第２開口部３２１を有する有底の第２容器３２と、水素化マグネシウムを含む水素発生シートまたは水素化マグネシウムの入った袋を収容する収容部と、外部から前記収容部につながる１個または複数の貫通孔２１とを有し、前記第１容器３１と前記第２容器３２とが形成する空間の内部に配置された水素発生器２０とを備える。【選択図】図１
