SYSTEM FOR PREVENTING UNAUTHORIZED UTILIZATION OF PORTABLE TERMINAL

PROBLEM TO BE SOLVED: To solve the problem that unauthorized utilization by a third person cannot be prevented unless an accessory unit is removed from a portable terminal device body.SOLUTION: Position detecting means 101 detects a present position of a portable terminal device 100 and transmits positional information indicating the present position to a monitoring device 200. When the positional information is sent from the portable terminal device 100, determination means 201 determines whether the portable terminal device 100 is present within a utilization permission range based on the positional information and utilization permission range information of the portable terminal device 100 recorded in a utilization permission range storage section 203. When the determination means 201 determines that the portable terminal device 100 is not present within the utilization permission range, remote control means 202 transmits a lock instruction to the portable terminal device 100. In response to the lock instruction, lock means 102 restricts use of the device 100 per se.