An illumination control apparatus including a controller which: in switching a first lighting mode to a second lighting mode when a combination of results of detections by occupancy sensors changes, compares a first priority level pre-assigned to the first lighting mode and a second priority level pre-assigned to the second lighting mode; if the second priority level is lower than the first priority level, maintains the first lighting mode for a predetermined amount of wait time from a moment when the combination of the results of the detections changes, and subsequently switches the first lighting mode to the second lighting mode; and if the second priority level is higher than the first priority level, switches the first lighting mode to the second lighting mode at the moment when the combination of the results of the detections changes.