In a monitor control system, an HMI (11 in FIG. 1) includes event list display means (16) for displaying an event list screen of list form, in which event names and alarm levels are contained as to faults and the like alarm events occurring in an object to-be-monitored (13), and storage means (17) for storing therein an alarm level table in which the alarm levels are set so as to correspond to time zones. When the alarm event occurs in the object to-be-monitored (13), the event list display means (16) determines the alarm level corresponding to the time zone in which an alarm event occurrence time is contained, on the basis of the alarm level table, so as to display the alarm level on the event list screen. Since the alarm level is changed depending upon the occurrence time, all alarm events can be recorded with unnecessary alarm events suppressed.