To find a bolt or screw left unfastened even when fastening has been made several times for one bolt or screw.

A fastening support device is equipped with a light emitting device 10, a camera 21, and a computer 20. The light emitting device 10 is mounted to a fastening tool 30. The camera 21 shoots a workpiece 40 for which the fastening is made. When the fastening is made for the workpiece 40 using the fastening tool 30, the computer 20 calculates a position where the fastening has been made using the fastening tool 30, based on an image of light emitted from the light emitting device 10 and captured by the camera 21.