RFID was first proposed as a technology for the automatic identification of objects. However, some recent RFID devices can provide additional information and can be used in other applications. Security requirement is essential in most of the applications. An essential research challenge is to provide efficient protection for RFID systems. Identity-based cryptography can provide encryption and digital signature and convenience in key management compared with traditional certificate-based PKI solution. In this paper, a security management solution for the RFID system is proposed by using identity-based cryptography.