ELECTRONIC KEY SYSTEM

An electronic key system installed in a vehicle includes: a first wireless communication controller performing transmission of a predetermined radio signal, as a verification signal, via a first wireless communication to confirm presence or absence of each of a first portable device and a second portable device each of which is usable as an electronic key of the vehicle; a second wireless communication controller periodically performing transmission/reception of the radio signal via second wireless communication to and from each of the first portable device and the second portable device upon transmitting/receiving the verification signal; and an integrity controller integrally controlling an operation of each of the first wireless communication controller and the second wireless communication controller.