A voice conference apparatus includes a sound collecting unit and a loudspeaker, while the sound collecting unit has a directional polar sensitivity characteristic which has a higher sensitivity with respect to sounds which are radiated from at least one direction, as compared with sounds radiated from other directions. The sound collecting unit of the voice conference apparatus has a plurality of omnidirectional microphones, and forms a desirable sensitivity characteristic. Since the omnidirectional microphones are employed, aging changes and fluctuations contained in the sensitivity characteristics of the respective sound collecting units can be reduced, so that the sensitivity characteristics thereof can become stable, and thus, full duplex communications with higher qualities can be carried out.