A portable sterilizing device for sterilizing at least one of a feeding bottle, a nipple, a bottle stopper, and a cap comprises: a sterilization covering body and a containing bottle. The sterilization covering body includes a covering member and a sterilizing member provided on the covering member, a UV-light emitting unit of the sterilizing member is emitting the UV light in a covering direction. The containing bottle includes a body portion and a connecting portion extensively formed from the body portion, the body portion covering the covering member along the covering direction in a manner that the connecting portion is attached to the attaching portion so as to form a containing space that faces toward the UV light for the sterilization. Thus, the portable sterilizing device has the advantages of small size and low power consumption, and therefore it is convenient for baby caretaker to portably carry it.
