A method of readily realizing electronic payment service at low cost with a high level of convenience and security for a consumer is disclosed. A personal information input terminal notifies a purchase price, an MSN (Mobile Subscriber Number) of an MS (Mobile Station), and personal information for identifying a purchaser through a public mobile communication network to request payment processing. A payment center device compares the information from the personal information input terminal with personal information stored in the device to determine whether the purchaser is qualified for electronic payment. If the purchaser is qualified for electronic payment, the payment center device notifies the MS of the purchase price with the MSN to request the purchaser to verify the purchase price. Upon notification from the MS that the purchase price is verified, the payment center device notifies an HLR (Home Location Register) over the public mobile communication network of the purchase price to request update of accounting information in order to collect the purchase price together with the charge for the MS. After the request for update of accounting information, the payment center device notifies a store that the electronic payment is completed.