For constructing a ubiquitous network, the highspeed wireless LAN (WLAN) attracts attention as an infrastructure for global access. However, some issues are impeding further adoption of the technology, in particular, security problems including user authentication, message compromising, password theft, connection hijacking, etc. In this paper, we discuss a fast authentication method of mobile ubiquitous terminals in WLAN. To achieve an efficient access control between Access Points (APs) and mobile terminals and sharing of a session key between terminals, we propose a new user secure authentication method and a session key distribution protocol based on service ticket issuing system.