A network-side device and a macro base station to micro base station switching method relate to a universal mobile telecommunications system. The method includes: multiplexing part of scrambling codes in reserved scrambling codes to micro base station cells, and configuring them to a user equipment; a network side creating a SNF−SFN relation list between various base station cells according to existing determined neighbor cell relations and cell synchronization information in a measurement report by the user equipment; when the user equipment reports a switching measurement report of a target cell, the network side determining a target cell in actual switching and performing the switching according to the scrambling code information in the switching measurement report, TM and OFF information in the cell synchronization information and the SFN−SFN relation list. The embodiment of the present invention further discloses a network-side device.