Methods for switching an eNB by a user equipment, eNBs and user equipments relate to a mobile communication system deployed in a heterogeneous network. The embodiments of the present invention disclose a method for switching an eNB by a UE, including: when a master eNB of the UE in dual connectivity is switched, a target eNB determining that the UE keeps a connection and configuration with a secondary eNB; and the target eNB establishing a connection with the UE when the UE keeps the connection and configuration with the secondary eNB. The embodiments of the present invention further disclose other three methods for switching the eNB by the UE and corresponding eNBs and user equipments. In the technical schemes of the present application, during data transmission and/or movement of the UE, the user plane between the UE and the accessed secondary eNB will not be interrupted, i.e., the data can be transmitted sequentially when the master eNB which the UE accesses is changed. Therefore, the performance and throu