To provide a prepaid system using a rewritable recording medium which can economically and easily provide prepaid services and improve the reliability by using a rewritable recording medium as a prepaid card.

A user 3 sets the rewritable recording medium 1 issued by a prepaid terminal 5 on a client terminal 7, accesses a provider center 9 through a network 15, and transfers the prepaid information recorded on the rewritable recording medium 1 to the provider center 9. The provider center 9 once receiving the prepaid information transfers the prepaid information to a prepaid center 11 so as to confirm its adequacy. The prepaid center 11 checks the prepaid information and performs a desired process when confirming the adequacy to rewrite and send the prepaid information back to the user 3 according to the process.