Three-dimensional intrusion detection system and three-dimensional intrusion detection method

The purpose of the present invention is to enable an observer to easily perform work of checking that a detection is not erroneous, whether intrusion detection is operating normally, and so forth as necessary, and to enable an observer to efficiently carry out observation work. In the present invention, an observation area is captured using at least two cameras disposed so as to be separated from each other, a plurality of camera images are obtained, three-dimensional measurement is performed in which a three-dimensional position of an object inside the observation area is measured by a three-dimensional measurement unit on the basis of the camera images, and three-dimensional information regarding the observation area is generated. An intrusion detection unit detects an object that has intruded into the observation area on the basis of a change in the three-dimensional information. An image generating unit generates a map image that visualizes the three-dimensional information and a mark image that indicates the object that has intruded into the observation area. The image generating unit outputs an observation screen in which an image selected by an input operation of a user from among the camera images and the map image, and the mark image are displayed.