A monitoring system according to the present invention includes a detecting unit, a tracking unit, a place judging unit and a reporting unit. When a pass unpermitted material that is not permitted to pass through a pass monitoring point passes through the pass monitoring point, the detecting unit detects the pass unpermitted material as a fraudulent passing material. The tracking unit tracks a position of the fraudulent passing material detected by the detecting unit. The place judging unit judges whether or not the fraudulent passing material exists inside a predetermined area. The reporting unit visibly reports the position of the fraudulent passing material and the judged result by the place judging unit.