The operation method of integrated control system according to an embodiment of the present invention comprises the steps of: providing an event detection request to the video analysis server; detecting an event by analyzing videos from at least one camera which are allocated to each video analysis server in accordance with default configuration; selecting at least one correlated camera corresponding to event-detecting camera by analyzing table information stored in the monitoring client as well as the event detection result; newly allocating the correlated camera to the at least one video analysis server; and detecting an event in each of the video analysis server by analyzing videos from the newly-allocated correlated camera.