A message sending method, comprising: determining (S302) to release or modify a first data radio bearer or a designated network element; and sending (S304) a first message to a first network element, wherein the first message carries a cause value for releasing or modifying the first data radio bearer or the designated network element, the cause value is used for the first network element to perform reconfiguration management of a bearer type of the first data radio bearer or a bearer type of a data radio bearer on the designated network element; characterized in that the method further comprises: in a case where the bearer type of all data radio bearers established by the designated network element for a designated user equipment is a secondary cell group, SCG, inter-NB bearer, which is a DRB bearer having a UP interface terminated on the second network element, and a lower-layer entity of the L2 protocol stack only and completely located in the first network element, determining whether to establish or delete at least one object of following objects: a lower-layer entity, a serving cell, or a signaling radio bearer between the designated network element and the designated user equipment, wherein the lower-layer entity comprises a radio link control, RLC, entity, and a medium access control, MAC, entity. determining (S302) to release or modify a first data radio bearer or a designated network element; and sending (S304) a first message to a first network element, wherein the first message carries a cause value for releasing or modifying the first data radio bearer or the designated network element, the cause value is used for the first network element to perform reconfiguration management of a bearer type of the first data radio bearer or a bearer type of a data radio bearer on the designated network element; characterized in that the method further comprises: in a case where the bearer type of all data radio bearers established by the designated network element for a designated user equipment is a secondary cell group, SCG, inter-NB bearer, which is a DRB bearer having a UP interface terminated on the second network element, and a lower-layer entity of the L2 protocol stack only and completely located in the first network element, determining whether to establish or delete at least one object of following objects: a lower-layer entity, a serving cell, or a signaling radio bearer between the designated network element and the designated user equipment, wherein the lower-layer entity comprises a radio link control, RLC, entity, and a medium access control, MAC, entity. in a case where the bearer type of all data radio bearers established by the designated network element for a designated user equipment is a secondary cell group, SCG, inter-NB bearer, which is a DRB bearer having a UP interface terminated on the second network element, and a lower-layer entity of the L2 protocol stack only and completely located in the first network element, determining whether to establish or delete at least one object of following objects: a lower-layer entity, a serving cell, or a signaling radio bearer between the designated network element and the designated user equipment, wherein the lower-layer entity comprises a radio link control, RLC, entity, and a medium access control, MAC, entity. <EOS>