A system is provided for supporting cash currency exchange. The system included a server, a first client requesting cash-currency-exchange service, and at least one second client providing the cash-currency-exchange service. The first client sends an exchange-service request of cash currency to the server. The server receives the exchange-service request, obtains the at least one second client, and pushes an exchange-service item corresponding to the exchange-service request to the at least one second client. The second client receives the exchange-service item, and sends a confirmation response to the server. The server pushes information about the at least one second client sending the confirmation response to the first client; and the first client displays the obtained information about the second client, determines a second client as a target client, and triggers an eWallet of the first client to transfer a specified amount to an eWallet of the target client.