A cell selection system selects a cell to be used for communications by a mobile terminal in a network having a cell of a mobile phone network and WLAN cells included in the cell. Broadcast information including cell selection information is transmitted in the cell of the mobile phone network. This cell selection information has cell change judgment parameters whose patterns are less than the WLAN cells. The mobile terminal reads the cell selection information from the broadcast information of the mobile phone network, determines a parameter to be used for the judgment on cell selection of a WLAN cell, and judges whether the cell can be changed or not. The cell reselection system restricts the amount of data in the broadcast information even with an increase in the number of WLAN cells included in the cell of the mobile phone network.