An access control method and system and an access point. When a fault occurs in an access controller (AC), an access point (AP) configures a network-layer interface of the AP according to an Internet Protocol (IP) address and a media access control (MAC) address of the AC that are obtained by means of pre-learning, and then the AP routes a received packet to a Web server on a wireless local area network (WLAN) using the configured network-layer interface, where the packet is used by a first station (STA) to request to access an external server. Therefore, interconnection and interworking among wireless local area networks are implemented, and a breakdown of a wireless local area network caused in a centralized network architecture due to occurrence of a fault in an AC is avoided.