A method and apparatus for performing handover on a voice call between a packet network system and a circuit network system is provided. Considering a communication environment where a UE cannot simultaneously use radio resources of both the next generation mobile communication system (LTE) and the legacy mobile communication system (e.g., GSM/WCDMA), the present invention proposes an SCSE for performing signal translation between the packet switched network and the circuit switched network and anchoring a voice call in the application level, and supports a continuous voice call using the SCSE.