A system for adult verification in a mobile RFID environment and a method thereof, more particularly, a system which strongly protects privacy and a method thereof are provided. The system comprising a RFID tag, a user terminal, an adult verification request processor, and a content provider (CP) includes: a rating information reader reading adult verification rating information of adult content recorded in an RFID tag; an adult verification rating determiner determining a final rating of the read rating information; and a service rating verification validity checker determining whether the adult content corresponding to the final rating is provided to a user of the terminal on the basis of the determined final rating and the age of the user.