The invention provides a WiFi sharing method and a server based on a block chain. The method comprises the following steps: acquiring WiFi connection request information sent by a WiFi using terminal;obtaining WiFi connection request information sent by a WiFi using terminal; obtaining WiFi connection request information from the WiFi using terminal. According to the WiFi connection request information, sending resource information and signature information of WiFi to be connected to the WiFi using terminal, so that the WiFi using terminal establishes a connection with the WiFi sharing terminal according to the resource information of the WiFi to be connected and the signature information, thereby using the WiFi to be connected generated by the WiFi sharing terminal. The invention provides a block chain-based WiFi sharing method and a server, By designing a decentralized form of WiFi sharing platform based on block chain, which improves the security of WiFi sharing network, Compatiblewith public WiFi and private WiFi, WiFi providers are authenticated and WiFi users are billed to make WiFi providers profitable, WiFi resources that motivate WiFi sharing and provide convenience to users are realized, user WiFi information is protected and user privacy data is protected.