To efficiently and accurately detect the direction of a sound source, even when detecting the direction of a sound source at a resonant location.

In a sound source direction detection apparatus 100, voice input devices 110a-110c acquire sound data from the source, and a voice recognition engine part 120a determines whether the sound data contains prescribed speech data. In the case that the voice recognition engine part 120a determines that the sound data contains the prescribed voice data, a voice start point is retrieved, and a direction detection engine part 120b determines the correlation function of each piece of prescribed voice data, in a section between the voice start point and the arrival time of reverberation sound acquired from a distance sensor 130 to detect the direction of the sound source.