A method for use in a mobile station which is adapted to perform wireless communication with two base stations, the method comprising: for a wireless communication with each of the two base stations, respectively, performing reception of a Common Pilot Channel (CPICH) received from each of the two base stations, respectively, performing reception of a High Speed-Shared Control Channel (HS-SCCH) received from each of the two base stations, respectively, performing reception of a High Speed-Physical Downlink Shared Channel (HS-PDSCH) received from each of the two base stations, respectively, in accordance with the reception of the High Speed-Shared Control Channel, and performing a transmission of an ACK or NACK signal, indicating the reception results of data in the High Speed-Physical Downlink Shared Channel, to each of the two base stations, respectively, in response to the High Speed-Physical Downlink Shared Channel; and performing a transmission of CQI information corresponding to the reception quality of a downlink signal, to each of the two base stations, respectively; during a handover from one of the two base stations as a handover source base station (6 1) to the other of the two base stations as a handover destination base station (6 2), performing control for starting the reception of the High Speed-Shared Control Channel from the handover destination base station before completing the reception of the High Speed-Physical Downlink Shared Channel from the handover source base station. for a wireless communication with each of the two base stations, respectively, performing reception of a Common Pilot Channel (CPICH) received from each of the two base stations, respectively, performing reception of a High Speed-Shared Control Channel (HS-SCCH) received from each of the two base stations, respectively, performing reception of a High Speed-Physical Downlink Shared Channel (HS-PDSCH) received from each of the two base stations, respectively, in accordance with the reception of the High Speed-Shared Control Channel, and performing a transmission of an ACK or NACK signal, indicating the reception results of data in the High Speed-Physical Downlink Shared Channel, to each of the two base stations, respectively, in response to the High Speed-Physical Downlink Shared Channel; and performing a transmission of CQI information corresponding to the reception quality of a downlink signal, to each of the two base stations, respectively; performing reception of a Common Pilot Channel (CPICH) received from each of the two base stations, respectively, performing reception of a High Speed-Shared Control Channel (HS-SCCH) received from each of the two base stations, respectively, performing reception of a High Speed-Physical Downlink Shared Channel (HS-PDSCH) received from each of the two base stations, respectively, in accordance with the reception of the High Speed-Shared Control Channel, and performing a transmission of an ACK or NACK signal, indicating the reception results of data in the High Speed-Physical Downlink Shared Channel, to each of the two base stations, respectively, in response to the High Speed-Physical Downlink Shared Channel; and performing a transmission of CQI information corresponding to the reception quality of a downlink signal, to each of the two base stations, respectively; during a handover from one of the two base stations as a handover source base station (6 1) to the other of the two base stations as a handover destination base station (6 2), performing control for starting the reception of the High Speed-Shared Control Channel from the handover destination base station before completing the reception of the High Speed-Physical Downlink Shared Channel from the handover source base station.