Abstract: In this paper, we propose a novel three-party authentication and key exchange protocol without using a timestamp based on chaotic maps. The proposed protocol requires neither symmetric nor asymmetric cryptosystems. Therefore, the computation complexity of the protocol is reduced and the efficiency of the protocol is improved. In addition, a convenient mechanism for updating user keys is provided, which improves the security of the protocol. Furthermore, the security analysis and performance evaluation are presented in the paper. In comparison with the related protocols, the proposed scheme is secure under certain types of attacks. It also has fewer transmissions and lower computational cost. Accordingly, it is feasible for real world applications.