PURPOSE: To enable position of a sound source to be localized by receiving supersonic wave from the sound source with a plurality of cruising bodies and by performing integral treatment of the received information which is obtained by each cruising body at a mother ship side which is connected to each cruising body with an optical cable.

CONSTITUTION: Information on a receiver, an attitude sensor, and a speed sensor which are mounted on a cruising body 2 is converted to light signal, is transmitted through an optical cable 3, reaches a mother ship 1, is converted to electrical signal at a side of the mother ship 1, and supersonic wave time difference, phase difference calculation, and cruising body receiving point position calculation etc. are performed by an operation control device within the mother ship 1, and a position of a sound source 4 is calculated from these calculation results, thus achieving a highly accurate position localization since controls is made to maintain an interval between the cruising bodies 2 to be a layout interval which is suitable for measuring position of the sound source 4.