A battery fold structure of an electronic device includes a device proper and at least one battery. The device proper has battery compartments and movable structures corresponding in position thereto, respectively. Each movable structure is movable relative to the device proper. At least one blocker is fixedly disposed at each movable structure. At least one bidirectional blocking element is fixedly disposed on the battery. The bidirectional blocking element has a first blocking portion and a second blocking portion. When the battery is received in one of the battery compartments, the first blocking portion of the bidirectional blocking element fixedly disposed on the battery is blocked by the blockers. When the battery is received in the other battery compartment, the second blocking portion of the bidirectional blocking element fixedly disposed on the battery is blocked by the blockers. Two batteries are mounted inside two battery compartments interchangeably and unlocked simultaneously.