Recently, many chaotic maps-based authenticated key agreement protocols using smart cards have been proposed. Unfortunately, tamper-resistant card readers make these protocols costly and unpractical. In addition, the digital signature scheme based on chaotic maps requires high computational resources. There exists security problem in publishing public keys which depend on signature schemes. In this paper, we will present a novel authenticated key protocol without smart cards while using extended Chebyshev maps. The proposed protocol eliminates the process of publishing the public key. Security and performance analysis show that our protocol can resist various attacks and yet is reasonably efficient. Therefore, our protocol is more suitable for practical applications.