Abstract—Many key agreement protocols based on chaotic maps have been proposed to guarantee secure communications in the network. Recently, Wang et al. proposed a new key agreement protocol based on chaotic maps. But some issues exist in this protocol, such as anonymity, key distribution and management, and password problems. In order to improve the performance of Wang et al.’s protocol, this paper proposes an optimized protocol based on Chebyshev polynomials, which can preserve user anonymity, guarantee mutual authentication and resist different attacks. The explicit analysis demonstrates that our protocol is secure, efficient and applicable.