Abstract: A cordless telephone system includes a base unit having a first handset, a second handset, an interruption replying unit, and a switching unit. A first multiple-party call is implemented between a first caller on the first handset, a second caller on the second handset, and an external caller on the outside line. A second multiple-party call is implemented between the first caller, the second caller, and an interrupting caller on the outside line. An interruption replying unit outputs a first replying signal and a second replying signal in response to a first caller's instruction and a second caller's instruction produced when the interrupting caller calls the base unit during the first multiple party call. A switching unit disconnects the second handset from the outside line if the first replying signal is outputted earlier than the second replying signal, and disconnect the first handset from the outside line if the second replying signal is outputted earlier than the first replying signal.