A system capable of charging up electronic money cards using a credit card is provided. A PIN is authenticated between a card terminal and the credit card. The card terminal transmits to a credit company server an authentication result, amount information indicating an amount with which to charge up, and a credit card number of the credit card. After billing, the credit company server transmits the amount information and the credit card number to an electronic money server. The electronic money server identifies an electronic money card based on the credit card number. The electronic money server generates amount change information for adding the amount with which to charge up to “VALUE”, and transmits the amount change information to the card terminal. The electronic money card updates the amount of “VALUE” stored therein to an amount specified by the amount change information.