Provided is a portable rechargeable power supply device such that major accidents such as from overcharging due to a hazard prevention means being damaged by rain water, or the like can be prevented from occurring. This portable rechargeable power supply device comprises a lithium-ion battery (11), an assembled circuit board (20), and a case (40). Two terminals (31a, 31b), a hazard prevention circuit unit (26), and the like, are provided on the assembled circuit board (20). A terminal housing case portion (416) of the case (40) houses a first portion of the assembled circuit board (20), which is provided with the two terminals (31a, 31b). A main body housing case portion (417) of the case (40) houses the lithium-ion battery (11), and a second portion of the assembled circuit board (20), which is provided with the hazard prevention circuit unit (26), and the like. The terminal housing case portion (416) and the main body housing case portion (417) are separated by a divider plate (414) and a shelving plate (415a). A gap between the divider plate (414) and the assembled circuit board (20) is closed by a gasket member (61).