Circuit domain fallback method and user equipment

The embodiment of the invention provides a circuit domain fallback method and user equipment, and relates to the field of communications. The circuit domain fallback method and the user equipment can shorten time delay and improve user experience. The method comprises the steps that a request message is sent to an LTE network, wherein the request message is used for requesting the LTE network for conducting CS voice services so as to enable the LTE network to send a CS voice service fallback response message to the user equipment, and the CS voice service fallback response message is used for notifying the user equipment to conduct CSFB from the LTE network to a GSM network; after the CS voice service fallback response message sent by the LTE network is received, system messages (SI1 and SI3) or a system message SI3 in a target cell in the GSM network is obtained; then the user equipment resides in the target cell according to the system messages or the system message, and a CS registration procedure is initiated according to the system messages or the system message so as to conduct the CS voice services.