An account registration method in a Digital Enhanced Cordless Telecommunications (DECT) network cluster system includes: establishing communication with a DECT host through a DECT network cluster constructed in advance; receiving first account information allocated by the DECT host; initiating registration to a server according to the first account information, and obtaining a first registration result; sending the first registration result to the DECT host; if the first registration result is that the registration is successful, entering a first mode; if the first registration result is that the registration is not responded to, obtaining a second registration result fed back by the DECT host; if the second registration result is that the registration is successful, entering a second mode, where in the second mode, the DECT device sends SIP signaling to the DECT host so that the DECT host forwards the SIP signaling.