A network card game in which a user purchases actual trading cards from a game planning company via a store or cellular phone agency. The user can transfer ownership of the card in a virtual card game space established by a service provider, separately from the actual trading cards. The card transfer In the virtual card game space enables the release of damaged cards which were damaged in a network card game, in addition to granting a point to a transfer source person. When the card is transferred to a friend, for example, and returned from the friend immediately after the transfer, the state of the damaged card returns to the normal state, and It becomes possible to use the card in a game soon. If logs of the transfer process are held, they can be used for various marketing.