A biological information monitoring system includes: a first monitoring device which includes a first displaying section and a first connector； a second monitoring device which includes a second connector； and a cable. The second monitoring device includes: a signal receiving section configured to receive a measurement signal related to biological information； and a second displaying section on which information corresponding to the measurement signal is displayed. When communication between the first and second connectors via the cable is established, the second displaying section is set to a non-display state, and the information corresponding to the measurement signal is displayed on the first displaying section.
