Recently use of RFID(Radio Frequency Identification) tends to be rapidly increased and will be also extended throughout the whole life. Using radio-frequency data can be recognized automatically in the RFID system is vulnerable to personal information protection or security. And passive tags have a hardware problem is the limit for applying cryptographic. This paper presents an authentication protocol using AES and Nounce. After completing mutual authentication server to access and strengthen security vulnerability to the use of the Nounce, because safety in denial of service attacks.