A transaction method includes: receiving, by a secure function module of a transaction terminal, a first transaction message sent by a transaction application module, where the first transaction message includes a first identifier and/or a secure transaction data requirement parameter; obtaining, by the secure function module, secure transaction data according to the first transaction message, or the first transaction message and a second identifier, where the second identifier is used to uniquely identify the secure function module; sending, by the secure function module, the secure transaction data to the transaction application module; and sending, by the transaction application module, a second transaction message to an acquiring terminal, where the second transaction message includes the secure transaction data, the first identifier, and a third identifier, and the third identifier is used to identify the transaction terminal.