A method, system, and mobile terminal for processing Voice over WiFi (VoWiFi) calls for a mobile terminal is proposed. The method includes pre-performing VoWiFi registration and controlling switches between WiFi access points (APs) during a communication state and an idle state under a VoWiFi network; forbidding the mobile terminal to initiate switches between the WiFi APs in the communication state under the VoWiFi network, and switching to a cellular network to implement voice communication when the mobile terminal is unable to connect to a WiFi network; and initiating AP switches and checking a network connection state for an AP in the idle state under the VoWiFi network. The method ensures that quality of voice communication of the mobile terminal under a VoWiFi network will not affected by frequent switches between multiple WiFi APs.