An unauthorized communication establishment prevention system includes a measurement unit arranged in at least one of a terminal and a communication peer. The measurement unit implements an unauthorized communication detection function and obtains a measurement value corresponding to a distance between the terminal and the communication peer. The system further includes a process execution unit that controls initiation, based on a determination result of whether the measurement value is appropriate, of an authentication performed through wireless communication established between the terminal and the communication peer even when the terminal is not operated. The system further includes a monitoring unit that monitors a battery level of the terminal and a suspension unit that suspends the unauthorized communication detection function when the battery level of the terminal is less than a specified amount that is not a battery depletion level.