The present invention discloses a carrier configuration method and a device, and relates to the field of communications, to resolve a problem that dividing multiple component carriers into primary and secondary component carriers only is not conducive to management of an important secondary component carrier. In a specific solution, a carrier aggregation model is configured for UE, so that the UE performs data transmission with a network device according to the carrier aggregation model. The carrier aggregation model includes multiple component carriers, the multiple component carriers include at least one core carrier, and the at least one core carrier includes at least one primary core carrier. The core carrier has an uplink transmission function and a downlink transmission function. The primary core carrier has at least one of the following functions: a system message bearing function, a paging message bearing function, a semi-static scheduling parameter configuration function, a camping reference function, or an encryption reference function. The present invention is applied to a carrier configuration process.