Electronic transaction system capable of improving transaction safety and electronic transaction method

This invention discloses an electronic transaction system and its electronic transaction method, at least one credence issue unit can get at least one electronic credence which represents its credence issue department or the electronic credence of transaction mark and at least one personal radio-frequency label that represents its corresponding user by the user's need , and the application data about users can be stored in a communications delivering management unit, wherein the electronic credence can be stored in a carrying electronic device owned by users, and when users do shopping transaction, a sale treating apparatus on sale part reads the electronic credence and personal radio-frequency label separately, and connects with communications delivering management unit by a telecommunication apparatus, then the communications delivering management unit judges and decides if it allows continuing the subsequent transaction action or finishing this shopping transaction action according to electronic credence, personal radio-frequency label and application data.