An embodiment of the invention relates to the field of communication, in particular to a data transmission method and device based on a wireless network in order to realize management and monitoring for Wi-Fi (wireless fidelity) access terminals in Wi-Fi-to-LTE (long term evolution) scenes. According to the embodiment, a tunnel IP (internet protocol) corresponding to a terminal IP is determined according to a preset corresponding relation of the terminal IP and the tunnel IP; tunnel indication information capable of indicating the tunnel IP is determined according to the tunnel IP; the tunnel indication information is encapsulated outside to-be-processed data, and encapsulated data is obtained; the encapsulated data is sent to an AC (access controller). The tunnel indication information is encapsulated outside the data transmitted by the terminal and internet, so that the AC can determine the terminal IP corresponding to the received data transmitted between the terminal and the internet, and the AC can manage and monitor information corresponding to the terminal IP.