The present disclosure relates to connection establishment methods and apparatus. In one example method, a central unit (CU) function entity receives a first connection establishment request of a master device, where the first connection establishment request includes at least first identification information of a terminal, identification information of a first data radio bearer (DRB), identification information of a target cell, and interface information of the master device. The CU function entity sends a second connection establishment request to a distributed unit (DU) function entity to request the DU function entity to establish a connection to the master device, where the second connection establishment request includes at least second identification information of the terminal, the identification information of the first DRB, and the interface information of the master device.