A method of setting validity period of IC card, includes preparing IC card including change unit whose state changes with lapse of time starting from initial state without external power, measuring unit configured to measure state of change unit so as to generate information indicating whether or not validity period has elapsed, and operation unit configured to be operable if information indicates that validity period fails to have yet elapsed, and to be inoperable if information indicates that validity period has elapsed, preparing IC card case capable to house IC card by user, IC card case including identification unit configured to determine whether or not user is legitimate, performing user identification utilizing identification unit, when IC card is housed in IC card case, and transmitting signal to change unit in IC card depending on result of user identification, signal initializing change unit to initial state.