In the field of wireless communications technologies, a CA processing method and device, with a CA processing scheme, are applied to a network sharing scenario. A second cell is determined according to a first PLMN ID used by a CA user equipment in a first cell and a frequency supported by the CA user equipment, where the first cell is currently accessed by the CA UE, CA can be performed to aggregate a second PLMN ID supported by the second cell with the first PLMN ID used by the CA user equipment in the first cell, and a frequency used by the second cell can be supported by the CA user equipment. According to the determined second cell, a CA cell is configured for the CA user equipment.