A tire theft monitoring system which monitors theft of a tire mounted on a vehicle, the tire theft monitoring system comprising: a transmitter (11, 11B) attached to a tire and configured to transmit tire ID information for identifying the tire; a first database configured to store vehicle ID information for identifying a vehicle and rightful tire ID information which is tire ID information of a rightful tire mounted on the vehicle in association with each other; a second database configured to store the vehicle ID information and contact information of an owner of the vehicle identified with the vehicle ID information in association with each other; and a monitoring apparatus (14, 14B) mounted on a vehicle to be monitored and configured to monitor whether or not a tire mounted on the vehicle to be monitored has been stolen, wherein the monitoring apparatus comprises: a reader configured to perform near field communication with the transmitter attached to the tire mounted on the vehicle to be monitored, to acquire the tire ID information transmitted by the transmitter; and a controller configured to, in a case where the reader cannot acquire the tire ID information, determine that the tire identified with the tire ID information has been stolen, and make a notification to contact information stored in the second database in association with vehicle ID information of the vehicle to be monitored, characterized in that: in a case where the controller determines that the vehicle to be monitored is a stolen-tire mounted vehicle on which a tire other than the tire identified with the rightful tire ID information stored in the first database in association with the vehicle ID information of the vehicle to be monitored is mounted, on a basis of the tire ID information acquired by the reader, the controller refers to the first database to acquire vehicle ID information stored in association with the tire ID information acquired by the reader, and notifies the monitoring apparatus mounted on the vehicle identified with the acquired vehicle ID information of information regarding the stolen-tire mounted vehicle. a transmitter (11, 11B) attached to a tire and configured to transmit tire ID information for identifying the tire; a first database configured to store vehicle ID information for identifying a vehicle and rightful tire ID information which is tire ID information of a rightful tire mounted on the vehicle in association with each other; a second database configured to store the vehicle ID information and contact information of an owner of the vehicle identified with the vehicle ID information in association with each other; and a monitoring apparatus (14, 14B) mounted on a vehicle to be monitored and configured to monitor whether or not a tire mounted on the vehicle to be monitored has been stolen, wherein the monitoring apparatus comprises: a reader configured to perform near field communication with the transmitter attached to the tire mounted on the vehicle to be monitored, to acquire the tire ID information transmitted by the transmitter; and a controller configured to, in a case where the reader cannot acquire the tire ID information, determine that the tire identified with the tire ID information has been stolen, and make a notification to contact information stored in the second database in association with vehicle ID information of the vehicle to be monitored, characterized in that: in a case where the controller determines that the vehicle to be monitored is a stolen-tire mounted vehicle on which a tire other than the tire identified with the rightful tire ID information stored in the first database in association with the vehicle ID information of the vehicle to be monitored is mounted, on a basis of the tire ID information acquired by the reader, the controller refers to the first database to acquire vehicle ID information stored in association with the tire ID information acquired by the reader, and notifies the monitoring apparatus mounted on the vehicle identified with the acquired vehicle ID information of information regarding the stolen-tire mounted vehicle. a reader configured to perform near field communication with the transmitter attached to the tire mounted on the vehicle to be monitored, to acquire the tire ID information transmitted by the transmitter; and a controller configured to, in a case where the reader cannot acquire the tire ID information, determine that the tire identified with the tire ID information has been stolen, and make a notification to contact information stored in the second database in association with vehicle ID information of the vehicle to be monitored, characterized in that: in a case where the controller determines that the vehicle to be monitored is a stolen-tire mounted vehicle on which a tire other than the tire identified with the rightful tire ID information stored in the first database in association with the vehicle ID information of the vehicle to be monitored is mounted, on a basis of the tire ID information acquired by the reader, the controller refers to the first database to acquire vehicle ID information stored in association with the tire ID information acquired by the reader, and notifies the monitoring apparatus mounted on the vehicle identified with the acquired vehicle ID information of information regarding the stolen-tire mounted vehicle.