To present a region which is not fully monitored, provided is a monitoring device comprising a detection means, an estimation means, a determination means, and a presentation means. The detection means detects a person from an image. The estimation means estimates a region which is being viewed by the person who is detected by the detection means. On the basis of the region estimated by the estimation means, the determination means determines a region which requires special attention within a monitoring area. The presentation means presents information indicating the region which requires special attention determined by the determination means.