A method and an apparatus for advertising border connection information of autonomous system are disclosed. Moreover, the method includes: establishing and maintaining, by a border node of the autonomous system, the border connection information of the autonomous system; flooding the border connection information within the autonomous system; and receiving, by nodes of the autonomous system, the border connection information. The method and the apparatus for advertising border connection information of autonomous system of embodiments of the present invention may adapt to dynamic change of network topology, and dynamically advertise the border connection information of the autonomous system within the system in time, so as to optimize networks and improve quality of service of the networks.