Abstract: Disclosed are an electronic trading method and system, and a payment platform system. The electronic trading system comprises a merchant trading system used by a merchant, a trading gateway, a bank system, a payment gateway and a payment platform system. The merchant trading system comprises a terminal used by a user and a merchant trading server. The payment platform system communicates with the merchant trading system via the trading gateway and communicates with the bank system via the payment gateway. The payment platform system is configured to receive an agreement deduction request sent from the merchant trading system, to verify the agreement deduction request, and to communicate with the bank system so as to perform a deduction according to the agreement deduction request and a predetermined payment deduction agreement after the agreement deduction request passes verification.