Switching method and switching system of supporting closed subscriber group(CSG) in double-connection system

The invention discloses a switching method and a switching system of supporting a closed subscriber group(CSG) in a double-connection system. The switching method comprises steps that a first base station connected with user equipment(UE) is used to transmit a switching request message including information related to the user equipment in the first base station and/or a third base station; the switching request message is used for the second base station to determine whether the UE is allowed to be connected with a fourth base station and/or to be connected with the fourth base station as the member of the CSG or not as the member of the CSG.