PURPOSE: To provide a recording area sharing picture monitor device which shares a picture recording area effectively using a picture memory and presents a display picture easy to see.

CONSTITUTION: A shared picture memory 7a where the picture signal of each camera 2 or terminal separated from inputs corresponding to cameras 2 or lines corresponding to terminals is recorded, a monitor display means 22 which simultaneously monitors and displays plural recorded contents of the shared picture memory 7a, and a use storage memory 8 where use/disuse of each camera 2 is stored, are provided, and recording areas of the shared picture memory 7a are switched in accordance with stored use/disuse to record and display out pictures. The distinction of use/disuse is stored in every camera 2 or terminal, and identification information of the camera 2 or terminal is simultaneously displayed in the case of monitor display.