Abstract: In allusion to the metabolism problem of AS-level network topology, complex network was combined with statistics approach to analyze AS-level network topology data. The evolution about the quantities of node and edge, average degree of network, hierarchy of network were studied, and specific changes of the unstable node was found in process of node evolving of AS-level topology. Studies show that the nodes' connection is more and more closely, and the structure is more and more complex in the AS-level topology; during the evolution of appearing node, 90% of birth and unstable nodes (i.e. duration time ration is less than 1) will occur jitter continuously, but 10% of the stable nodes (i.e. duration time ration equals 1) grow into the big degree and high core nodes. Additionally, only 2% of disappearing nodes are dead in their evolution.