A method for transferring a video call between access networks, comprising: pre-negotiating, in a packet switching, PS, domain and through IP multimedia subsystem, IMS, signaling, a circuit switching, CS, video call parameter, to obtain a pre-negotiated CS video call parameter; and after a video call of a terminal is transferred from the PS domain to a CS domain, establishing a CS video call according to the pre-negotiated CS video call parameter; wherein the step of pre-negotiating, in the PS domain and through the IMS signaling, the CS video call parameter comprises: obtaining, by a Mobile Switching Center, MSC, server, information that is of the terminal and is required for establishing the CS video call, performing, according to the obtained information that is of the terminal and is required for establishing the CS video call, CS video call parameter pre-negotiation to obtain the pre-negotiated CS video call parameter, and sending the pre-negotiated CS video call parameter to the terminal; wherein the information that is of the terminal and is required for establishing the CS video call is carried in an IMS video call establishment request message initiated by the terminal in the PS domain, the IMS video call establishment request message carries an indication that the terminal supports single radio video call continuity pre-negotiation. pre-negotiating, in a packet switching, PS, domain and through IP multimedia subsystem, IMS, signaling, a circuit switching, CS, video call parameter, to obtain a pre-negotiated CS video call parameter; and after a video call of a terminal is transferred from the PS domain to a CS domain, establishing a CS video call according to the pre-negotiated CS video call parameter; wherein the step of pre-negotiating, in the PS domain and through the IMS signaling, the CS video call parameter comprises: obtaining, by a Mobile Switching Center, MSC, server, information that is of the terminal and is required for establishing the CS video call, performing, according to the obtained information that is of the terminal and is required for establishing the CS video call, CS video call parameter pre-negotiation to obtain the pre-negotiated CS video call parameter, and sending the pre-negotiated CS video call parameter to the terminal; wherein the information that is of the terminal and is required for establishing the CS video call is carried in an IMS video call establishment request message initiated by the terminal in the PS domain, the IMS video call establishment request message carries an indication that the terminal supports single radio video call continuity pre-negotiation. obtaining, by a Mobile Switching Center, MSC, server, information that is of the terminal and is required for establishing the CS video call, performing, according to the obtained information that is of the terminal and is required for establishing the CS video call, CS video call parameter pre-negotiation to obtain the pre-negotiated CS video call parameter, and sending the pre-negotiated CS video call parameter to the terminal; wherein the information that is of the terminal and is required for establishing the CS video call is carried in an IMS video call establishment request message initiated by the terminal in the PS domain, the IMS video call establishment request message carries an indication that the terminal supports single radio video call continuity pre-negotiation.