The earthquake site communication technologies are very important for the post-earthquake emergency and rescue work, with high requirements for convenient setup and stable data transmission. According to the real requirements, methods to establish the earthquake site communication network based on wireless mesh network (WMN) are proposed in this paper. A WMN is a special type of wireless ad hoc network and supports various wireless protocols. Some key issues (architecture, capacity, radio techniques, scalability, security, etc.) of WMN are discussed. On the basis of summarizing different applications supported by WMNs, an earthquake site communication network based on WMN is established. In such an application, various Wi-Fi clients are connected together and consequently facilitate the earthquake site rescue work. The methods are proved feasible and meaningful for real earthquake emergency and rescue work.