The disclosure provides a method and a device for implementing network coexistence and a mobile terminal. The method comprises: detecting whether a mobile terminal is in a wireless fidelity (Wifi) network connection state; and if so, switching the network connection mode of a data link according to whether the Wifi network is a valid network. According to the method and the device for implementing network coexistence and the mobile terminal provided by the disclosure, when the mobile terminal being in the Wifi network connection state is detected, the network connection mode of the data link is switched according to whether the Wifi network is a valid network, so that the coexistence of the Wifi network and the mobile communication network can be implemented and the user experience is improved.
