Electronic key system

An electronic key system comprising:

• a portable apparatus that is carried by an owner, the portable apparatus wirelessly transmitting an information signal including a portable apparatus information;
• an operation control device for controlling an operation of a predetermined operation object, wherein the operation control device receives the information signal transmitted from the portable apparatus;
• security means;
• an update control device for wirelessly transmitting a request signal in a private region of the owner of the portable apparatus, wherein the portable apparatus wirelessly transmits a response signal based on reception of request signal, wherein the update control device receives the response signal and the portable apparatus information that is included in the information signal from the operation control device;
• wherein the update control device has a counter for counting time or a value that represents the number of times that the portable apparatus is used for controlling the operation control device, wherein, when receiving the request signal, the portable apparatus controller resets the counter, wherein, when receiving the portable apparatus information, the update control device commands the operation control device to authorize the operation of the operation object if the counting value of the counter is equal to or less than a predetermined limit value, and wherein the update control device causes the security means to perform security if the counting value of the counter is in excess of the limit value.