This invention discloses a clock synchronized dynamic password security label validity real-time authentication system and method thereof, which comprises, the electronic label module, the user authentication terminal module, and the authentication service module. The electronic label module is used for generating the dynamic password data and displaying. The user authentication terminal module captures the dynamic password data generated by the electronic label module and the image data of the ID number of the electronic label module. After the analyzing processing, the text data is obtained, and then is sent to the authentication service module through the Internet. After receiving the text data, the authentication service module obtains the result of whether the first dynamic password data generating algorithm of the electronic label module is consistent with the second dynamic password data generating algorithm of the authentication service module. The result is returned to the user authentication terminal module.