A handover method, comprising: continuing, by a serving base station, allocating uplink and downlink transmission resource for a mobile terminal when sending a handover command to the mobile terminal (206, 306) enabling the mobile terminal keep a data communication with the serving base station after receiving the handover command, and meanwhile perform a random access process to a target base station (207, 307) to obtain uplink synchronization information of the target base station; wherein the mobile terminal performs the random access process to the target base station on a first carrier; the mobile terminal keeps a data communication with the serving base station on a second carrier; wherein the method further comprises: stopping, by the serving base station, allocating the uplink and downlink transmission resource for the mobile terminal on the second carrier when a communication terminating condition is met; and disconnecting the data communication between the mobile terminal and the serving base station on the second carrier; wherein stopping allocating the uplink and downlink transmission resource for the mobile terminal on the second carrier when a communication terminating condition is met comprises: stopping, by the serving base station, allocating the uplink and downlink transmission resource for the mobile terminal on the second carrier after the mobile terminal obtains the uplink synchronization information of the target base station on the first carrier; wherein the method further comprises: receiving, by the serving base station, a handover measurement result reported from the mobile terminal on the second carrier (201, 301); determining, by the serving base station, a target base station, and sending a handover request to the determined target base station (203, 303), after determining that it is required to perform a handover for the mobile terminal according to the received handover measurement result reported from the mobile terminal (202, 302); receiving, by the serving base station, a carrier number of the first carrier and a position of a random access resource block fed back from the target base station; and sending, by the serving base station, to the mobile terminal on the second carrier the carrier number of the first carrier and the position of the random access resource block fed back from the target base station enabling the mobile terminal execute the random access process using the first carrier and the random access resource block fed back from the target base station; the handover request comprises uplink carrier usage information of the mobile terminal; and the method further comprises: after receiving the handover request and determining that the mobile terminal is allowed to access (204, 304), selecting, by the target base station, the first carrier for the mobile terminal according to the uplink carrier usage information of the mobile terminal, and feeding back the carrier number of the first carrier and the position of the random access resource block to the serving base station through a handover request accept message (205, 305). continuing, by a serving base station, allocating uplink and downlink transmission resource for a mobile terminal when sending a handover command to the mobile terminal (206, 306) enabling the mobile terminal keep a data communication with the serving base station after receiving the handover command, and meanwhile perform a random access process to a target base station (207, 307) to obtain uplink synchronization information of the target base station; wherein the mobile terminal performs the random access process to the target base station on a first carrier; the mobile terminal keeps a data communication with the serving base station on a second carrier; stopping, by the serving base station, allocating the uplink and downlink transmission resource for the mobile terminal on the second carrier when a communication terminating condition is met; and disconnecting the data communication between the mobile terminal and the serving base station on the second carrier; receiving, by the serving base station, a handover measurement result reported from the mobile terminal on the second carrier (201, 301); determining, by the serving base station, a target base station, and sending a handover request to the determined target base station (203, 303), after determining that it is required to perform a handover for the mobile terminal according to the received handover measurement result reported from the mobile terminal (202, 302); receiving, by the serving base station, a carrier number of the first carrier and a position of a random access resource block fed back from the target base station; and sending, by the serving base station, to the mobile terminal on the second carrier the carrier number of the first carrier and the position of the random access resource block fed back from the target base station enabling the mobile terminal execute the random access process using the first carrier and the random access resource block fed back from the target base station; after receiving the handover request and determining that the mobile terminal is allowed to access (204, 304), selecting, by the target base station, the first carrier for the mobile terminal according to the uplink carrier usage information of the mobile terminal, and feeding back the carrier number of the first carrier and the position of the random access resource block to the serving base station through a handover request accept message (205, 305).