To efficiently output only a voice of a driver riding on a vehicle as an output waveform signal.

The sound source direction judging apparatus is provided with: a microphone 2 in which a phase is considerably changed in accordance with a direction of a sound source; a microphone 1 proximately located with a phase which becomes different from that of the microphone 2 in accordance with the direction of the sound source; and a phase comparator (judgement means) 3 for judging the direction of the sound source based upon the relationship of phases of waveform signals outputted from the respective microphones. The microphone unit controls output levels of the waveform signals from the microphones based upon the result judged by the phase comparator 3.