An electronic device having a fool-proof feature is provided, including a first magnet, an output terminal, a hall sensor and a power supply unit. The first magnet generates a magnetic field. The output terminal is disposed in the range of the magnetic field and is mated with an input terminal of a second electronic device. The hall sensor generates a hall voltage according to the magnetic field. The power supply unit is coupled to the output terminal and provides power to the output terminal according a control signal outputted from the hall sensor, in which the hall sensor outputs the control signal when the output terminal is coupled to the input terminal and the hall voltage exceeds a specific voltage, such that the power supply unit provides power to the output terminal according to the control signal, and the second electronic device receives power from the output terminal.