An object of the present invention is to provide a tooth bleaching device and a tooth bleaching kit capable of performing tooth whitening with high efficiency, that is, in a short time without demineralizing the teeth. An external member, a bleach precursor (I) containing chlorous acid or a salt thereof placed inside the external member, an acidifying agent (II) containing a substance whose aqueous solution is acidic, and an aqueous solution thereof A neutralizing agent (III) containing a substance showing basicity, a first partition wall located between the bleaching agent precursor (I) and the acidifying agent (II), and a bleaching agent precursor (I) or an acid. A device for bleaching teeth, comprising a second septum located between the agent (II) and the neutralizing agent (III), as well as such a device and a pressure-supplying member or an aqueous liquid A tooth bleaching kit including a supply member is used. [Selection diagram] FIG.【課題】本発明の目的は、歯を脱灰することなく、高効率で、即ち、短時間で歯のホワイトニングを実施できる歯の漂白用デバイス及び歯の漂白用キットを提供することにある。【解決手段】外部部材、外部部材の内部に載置された亜塩素酸もしくはその塩を含む漂白剤前駆体（Ｉ）、その水溶液が酸性を示す物質を含む酸性化剤（ＩＩ）、その水溶液が塩基性を示す物質を含む中和用剤（ＩＩＩ）、漂白剤前駆体（Ｉ）と酸性化剤（ＩＩ）との間に位置する第一隔壁、及び漂白剤前駆体（Ｉ）又は酸性化剤（ＩＩ）と中和用剤（ＩＩＩ）との間に位置する第二隔壁とを備えることを特徴とする歯の漂白用デバイス、並びに、このようなデバイスと、圧力供給部材又は水性液体供給用部材とを備える歯の漂白用キットを使用する。【選択図】図１０
