The Wireless Local Area Network (WLAN) is a new and developing technology and the security problem is always important in all networks; therefore, the security problems will be discussed in this article. The article firstly introduces the history of development of IEEE 802.11 and provides an overview of the Wireless LAN. The architecture of WLAN will be referred in next. Finally, the further of the wireless LAN will be prospected by this article. The Wireless Local Area Network (WLAN) is a new and developing technology and the security problem is always important in all networks; therefore, the security problems will be discussed in this article. The article initially introduced the history of development of IEEE 802.11 and provides an overview of the Wireless LAN. The architecture of WLAN will be referred in next. Finally, the further of the wireless LAN will be prospected by this article.