To provide a lost article searching system capable of using a generally widely spread short-range radio communication technology, and maintaining interchangeability by facilitating countermeasures only by correcting a software part.

A search side device 100 and a search reception side device 200 can communicate by using a generally widely spread short-range radio communication technology such as wireless LAN communication or Bluetooth communication. When the location of belongings which the search reception side device 200 is added to or integrated into is lost, the search reception side device 200 is called by using the short-range radio communication from the search side device 100. When the search data are identification data to its own destination, the called search reception side device 200 informs a user that at least the device 200 is present in a range reachable by radio by means of voice notice, ringing, emission, or response to the search side device 100 or the like.