The method comprises: setting up a independent HLRID for the standby HLR; adding the standby signaling of main HLR into the STP, and routing it to the standby HLR; the standby signaling from local number segment to local HLR signaling is adding into MSC/GW, and is routed to the HLR; the standby HLR is switched over to each net element through STP; when standby and main switches are switched, the STP interrupts the signaling link of the main HLR, and switches the signaling of main HLR to the standby HLR.