Position identification apparatus, position identification method, and position identification system and program

A position identification apparatus (10) is provided with the following: a first wireless communication information acquisition unit (11a) that causes a plurality of installed devices installed in a prescribed space to wirelessly communicate with each other and thereby acquires, for each installed device, first wireless communication information indicating a first physical quantity obtainable for each combination of installed devices; a memory unit (12) that stores the first wireless communication information acquired for each installed device by the first wireless communication information acquisition unit (11a); a second wireless communication information acquisition unit (11b) that causes the plurality of installed devices and a terminal located in the prescribed space to wirelessly communicate with each other and thereby acquires second wireless communication information indicating a second physical quantity obtainable for each combination of terminal and installed device; and a nearby installed device detection unit (11c) for detecting, from among the plurality of installed devices, an installed device having a first physical quantity close to a second physical quantity.