A bearer mapping method, applied to a base station, comprising: indicating, in an implicit or explicit manner, a mapping relationship between a bearer ID and a bitmap in a media access control layer control element, MAC CE, wherein the MAC CE is a control element for a duplication activation indication or deactivation indication, and the bearer ID is an ID of a bearer configured with a duplication function; the indicating, in the explicit manner, the mapping relationship between the bearer ID and the bitmap in the MAC CE comprises: indicating the mapping relationship between the bearer ID and the bitmap in the MAC CE through a high-layer signaling; characterized in that the indicating the mapping relationship between the bearer ID and the bitmap in the MAC CE through the high-layer signaling comprises: carrying, in a bearer establishment instruction, a mapping relationship between a bearer ID of a new bearer and the bitmap; and carrying, in a bearer releasing instruction, a mapping relationship between a bearer ID of a bearer to be released and the bitmap or the bearer ID of the bearer to be released or indication information indicating that the bearer does not have the duplication function; and carrying, in a bearer modification instruction, a mapping relationship between a bearer ID of a modified bearer and the bitmap. indicating, in an implicit or explicit manner, a mapping relationship between a bearer ID and a bitmap in a media access control layer control element, MAC CE, wherein the MAC CE is a control element for a duplication activation indication or deactivation indication, and the bearer ID is an ID of a bearer configured with a duplication function; the indicating, in the explicit manner, the mapping relationship between the bearer ID and the bitmap in the MAC CE comprises: indicating the mapping relationship between the bearer ID and the bitmap in the MAC CE through a high-layer signaling; characterized in that the indicating the mapping relationship between the bearer ID and the bitmap in the MAC CE through the high-layer signaling comprises: carrying, in a bearer establishment instruction, a mapping relationship between a bearer ID of a new bearer and the bitmap; and carrying, in a bearer releasing instruction, a mapping relationship between a bearer ID of a bearer to be released and the bitmap or the bearer ID of the bearer to be released or indication information indicating that the bearer does not have the duplication function; and carrying, in a bearer modification instruction, a mapping relationship between a bearer ID of a modified bearer and the bitmap. indicating the mapping relationship between the bearer ID and the bitmap in the MAC CE through a high-layer signaling; characterized in that the indicating the mapping relationship between the bearer ID and the bitmap in the MAC CE through the high-layer signaling comprises: carrying, in a bearer establishment instruction, a mapping relationship between a bearer ID of a new bearer and the bitmap; and carrying, in a bearer releasing instruction, a mapping relationship between a bearer ID of a bearer to be released and the bitmap or the bearer ID of the bearer to be released or indication information indicating that the bearer does not have the duplication function; and carrying, in a bearer modification instruction, a mapping relationship between a bearer ID of a modified bearer and the bitmap. carrying, in a bearer establishment instruction, a mapping relationship between a bearer ID of a new bearer and the bitmap; and carrying, in a bearer releasing instruction, a mapping relationship between a bearer ID of a bearer to be released and the bitmap or the bearer ID of the bearer to be released or indication information indicating that the bearer does not have the duplication function; and carrying, in a bearer modification instruction, a mapping relationship between a bearer ID of a modified bearer and the bitmap. <EOS>