The invention provides an IC (integrated circuit) card paying system and method as well as a multi-application IC card and a payment terminal. The invention has the following advantages: during offline transaction, the terminal and the IC card adopt an asymmetric key algorithm to authenticate offline data, and if the offline transaction is not approved, the terminal and the IC card carry out online transaction via a host, so the IC card paying system and method as well as the multi-application IC card and the payment terminal, which are disclosed by the invention, can be applied to machines and tools without online transaction environment and machines and tools, with online transaction environment, of standard merchants.