The liquid droplet spraying apparatus of the present invention includes a nozzle body which comprises a chamber for containing a predetermined amount of fluid supplied from an exterior, and a nozzle communicating with the chamber and spraying a liquid droplet of the fluid contained in the chamber to one side of the material to be printed; an electrode module unit which is arranged to be attached to or spaced apart from an outside of the nozzle body; an alternating current signaler which applies an alternating current signal to the electrode module unit; and a signal control unit which controls intensity and frequency of an output signal from the alternating current signaler.