An assembled battery reusing system for sorting an assembled battery including a plurality of single cells, to one of at least an assembled battery that can be shipped directly, or an assembled battery that is usable for recycling, or an assembled battery that is used for rebuilding, the assembled battery reusing system comprising: an assembled battery information acquisition unit configured to acquire information about the assembled battery; a rebuild candidate determining unit configured to determine based on the information about the assembled battery whether a retrieved assembled battery is a rebuild candidate, the information being acquired by the assembled battery information acquisition unit; a single cell amount determining unit configured to determine an amount of rebuilding-usable single cells included in the rebuild-candidate assembled battery determined by the rebuild candidate determining unit; and characterized by further comprising: an assembled battery demand information acquisition unit configured to acquire an amount of rebuilding-required single cells required to rebuild a required new assembled battery; and a determination unit configured to determine based on the amount of rebuilding-usable single cells and the amount of rebuilding-required single cells whether to send the rebuild-candidate assembled battery to a rebuilding process, the amount of rebuilding-usable single cells being determined by the single cell amount determining unit, the amount of rebuilding-required single cells being acquired by the assembled battery demand information acquisition unit. an assembled battery information acquisition unit configured to acquire information about the assembled battery; a rebuild candidate determining unit configured to determine based on the information about the assembled battery whether a retrieved assembled battery is a rebuild candidate, the information being acquired by the assembled battery information acquisition unit; a single cell amount determining unit configured to determine an amount of rebuilding-usable single cells included in the rebuild-candidate assembled battery determined by the rebuild candidate determining unit; and characterized by further comprising: an assembled battery demand information acquisition unit configured to acquire an amount of rebuilding-required single cells required to rebuild a required new assembled battery; and a determination unit configured to determine based on the amount of rebuilding-usable single cells and the amount of rebuilding-required single cells whether to send the rebuild-candidate assembled battery to a rebuilding process, the amount of rebuilding-usable single cells being determined by the single cell amount determining unit, the amount of rebuilding-required single cells being acquired by the assembled battery demand information acquisition unit. an assembled battery demand information acquisition unit configured to acquire an amount of rebuilding-required single cells required to rebuild a required new assembled battery; and a determination unit configured to determine based on the amount of rebuilding-usable single cells and the amount of rebuilding-required single cells whether to send the rebuild-candidate assembled battery to a rebuilding process, the amount of rebuilding-usable single cells being determined by the single cell amount determining unit, the amount of rebuilding-required single cells being acquired by the assembled battery demand information acquisition unit.