PURPOSE: To enable automatic inspection of a surface recession defect of a round surface to be inspected, by determining the quality of a body to be inspected, by comparing the number of pixels being discriminated and not receiving light with a reference value.

CONSTITUTION: A belt conveyor 13 conveys a body 14 to be inspected onto a jig 16. An arm 4 operates, takes hold of the body 14 by a chuck, runs onto an inspection stage 8 and sets the body thereon. The stage 8 rotates at about 15 rpm and the body 14 be inspected makes one and a little more revolutions, while reflecting a light emitted by a floodlight 10. Meanwhile, a CCD camera 11 senses the light, making image plane boundaries overlap each other at the timing of a shutter. An image controller counts the number of pixels for each window formed by dividing an image plane and, when the added number of pixels exceeds a reference value, it gives a command to a sequencer so as to exclude the body as a defective. Thereby the chuck is made to drop the body 14 into a hole 17. When the number does not exceed the reference value, the body is transferred as a nondefective onto a belt conveyor 18 and conveyed to a subsequent process.