Along with the large-scale proliferation of network and information technology, users can obtain the information resources conveniently via intelligent device. Authentication mechanism is a fundamental tool for ensuring secure communications and the validity of communicating party. In this paper, we propose a new authentication scheme for anonymous users using elliptic curves cryptosystem (ECC) which achieves mutual authentication and forward security. Specifically, we certify the validity of our proposal by employing BAN-logic, which is one of the important formal methods. Further, the performance comparison shows that our scheme is more suitable for application scenarios where efficiency and security concerned.