Mobile station with packet reordering function

Disclosed is a reordering method of sending packets, to which numbers indicating the packet order are added, to a mobile station from a base station, and rearranging the order of the packets at the mobile station. This reordering method comprises: a step of forwarding from a source base station to a target base station, packets, which have not been sent to the mobile station before a handover sequence, or packets, for which a confirmation response of right reception has not been received from the mobile station; a step of transmitting preferentially those packets from the target base station to the mobile base station and then transmitting packets received from a host station to the mobile station; a step of giving packets information indicating that the packets are jump packets when transmitting the packets to the mobile station that were received from the host station with the order jumped; and a step of deciding jump packets are not objects of reordering, and performing the reordering process for packets that are objects of reordering.