The implementation method for an identification system using dynamic barcode entails description for a system that comprises a smartphone, a barcode information access device on the merchant side, and a server of an identification agency. The implementation method described includes downloading a mobile application (app) for smartphone, and utilizing the app to upload identification information to server of the identification agency. When a user needs to be identified during a transaction, the aforementioned app is used to display two barcodes on the smartphone: one barcode represents the user's identification, and the other is a dynamic one that corresponds to the user's identification information and changes after a given time period. When both barcode information are read by barcode reader and send to the server of the identification agency, the said agency could easily compare its own information with the dynamically generated barcode information, which helps to distinguish whether the user is the original registrant.