Radio frequency identification (RFID) systems rely on the significant technology of remote, automatic identification with small, low-cost RF elements to complete RF communications securely among all entities. This technology must ensure that secret information or data communicated via radio transmission are not vulnerable to intentional interception, modification for tracing the individual tag holder, or the attachment of any item. With the increase in the number of applications of RFID systems, security and privacy problems have become the focus of significant concern. In this paper, we propose an authenticated RFID security mechanism based on chaotic maps that guarantees a mutually authenticated process and uses a simple and robust chaotic cryptosystem to implement a practical RFID mechanism. The security of the transmitted information and the privacy of personal information or data were our main concerns in the proposed scheme. Also, we have provided detailed information concerning authentication proof and security aspects of our new design. Copyright © 2013 John Wiley & Sons, Ltd.