A quality memory unit remembers a quality table in which qualities of communication with radio base stations are arranged according to identification information of the radio base stations. A processing unit determines, based on the quality table in the quality memory unit, a selecting radio base station to select a switching radio base station to be a connection destination after switching. The processing unit sends the quality table to the selecting radio base station when switching the connection destination radio base stations. A mobile station communication unit receives identification information specifying the switching radio base station selected based on the quality table sent from the processing unit and sends a connection request to the switching radio base station specified by the identification information.