To analyze the cause if an event occurred to a plurality of monitoring targets. A monitoring computer 101 includes a general rule storing part 136 configured to store a general rule, wherein the general rule previously associates a first event which can occur in any of the plurality of monitoring targets and a second event which can cause the first event, an correlation rule generating part 129 configured to generate an correlation rule, wherein the correlation rule is created based on the general rule and configuration information, and in the case where a predetermined number or more of events corresponding to the second events are detected, the correlation rule indicates that an event corresponding to the first event will occur, and an analyzing part 125 configured to analyze a cause of an event indicated by the event information based on received event information and the correlation rule.