Emergency call method, and emergency callback method and system

The invention provides an emergency call method, and an emergency callback method and system. The emergency callback system comprises an emergency call acceptance center (PSAP), an agency call session control function entity (P-CSCF), an emergency call session control function entity (E-CSCF), and an application server (VoLTE AS). The P-CSCF enables an IMS emergency call number and a common number to be synthesized into an emergency identification number, and the emergency identification number is transmitted to the PSAP through the E-CSCF and the VoLTE AS. When the PSAP calls back a callback number and the application server judges that the callback number is an emergency identification number, the callback number is directly transmitted to the P-CSCF through the E-CSCF, and the P-CSCF searches the common number corresponding to the emergency identification number and then directly calls back user equipment corresponding to the common number. 本发明提供了种紧急呼叫方法、紧急呼叫回呼方法及系统，其中，所述紧急呼叫回呼系统包括：紧急通信受理中心(PSAP)、代理呼叫会话控制功