A user device receives the content, and pays a content fee, based on the usage control policy of the content, by electronic money up to the allowable amount of money set in an issue log. The user device then creates a usage log including a content identifier and sends it to a service provider. The service provider creates a receive log based on the usage log, and sends it to a clearing center. The clearing center performs settlement processing for the electronic money based on the receive log, and sends a transfer request to an account management institution. By performing the above-described series of processing by using encrypted data, the settlement of the content usage fee is safely performed.