A registration method includes sending, by a terminal, a first message to the AMF entity, where the first message includes first information, first network slice selection information, second network slice selection information, and information for requesting to establish a protocol data unit (PDU) session. The first network slice selection information is used by the AMF entity to select a first session management control function (SMF) entity, and the second network slice selection information is used by the AMF entity to select a second SMF entity. The method further includes receiving, by the terminal, a second message from the AMF entity, where the second message includes second information, and the second information includes PDU session establishment accept information.