Disclosed herein are an authentication and payment system and method. The authentication and payment system of the present invention includes an issuer server, an issuer information management intermediate server, an acquirer server and a payment server. The issuer server issues, manages and operates payment means. The issuer information management intermediate server manages URL information required to access domestic and foreign issuer servers. The acquirer server performs payment approval and performs acquisition and settlement for member stores. The payment server intermediates between the issuer server and the acquirer server to provide an authentication and payment service in response to a request from a terminal of the merchant. Accordingly, the present invention can provide a safe and convenient payment process with respect to payment means, such as credit cards, electronic money or mobile phone micro payment that can be selected between a purchaser and a merchant.