Embodiments of the present invention relate to the field of wireless communications technologies, and in particular, to a CA processing method and device, so as to provide a CA processing scheme applicable to a network sharing scenario. In the embodiments of the present invention, 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 a cell that the CA UE currently accesses, CA can be performed on a second PLMN ID supported by the second cell and 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; and, according to the determined second cell, a CA cell is configured for the CA user equipment.