Abstract: Wireless mesh network is a new wireless multi-hop networking which evolves from ad hoc network and has the advantages of more coverage and more capacity，so it suits for wireless access backbone.802.11s task group，formed by IEEE，is responsible for mesh expansion of 802.11 ESS structure.For many key technologies are immature，it severely impacts the development of 802.11s standard.For better understanding the research and development，this paper across-the-broad relates the key technologies in 802.11s.According to aspect of the performance，shortcoming and challenge of 802.11s mesh network are pointed out.