To provide an unevenness detector which can accurately detect a body through simple processing.

Two CCD cameras 10 and 20 are installed so that an optical axes of respective lenses are perpendicular to a reference surface A and image pickup surfaces are parallel, a control part 30 controls positions of the image pickup surfaces so that the same image is formed on the image pickup surfaces of the two CCD cameras 10 and 20, and a decision part 40 calculates the difference in a density value between images picked up by the two CCD cameras 10 and 20 to decide whether there is a recessed part or a projection part about the reference surface A, thereby detecting the body.