To create a presence as if a real object exists there by giving a depth to a video in a device for spatially displaying a two-dimensional video by using a half mirror.

In this spatial video display device, a virtual image 4 is formed by reflecting a main video 2 by a half mirror 3, and the video 6 of the shadow of a subject is displayed behind the image 4 by leaving a specified space in between, then the depth and reality are given to the video by the contrast of the main video and the shadow video. Besides, an image processor generating the shadow video from the main video is added to the device at request.