An inspecting device and an inspecting method enabling better precision inspection for a processing region formed on a surface of a semiconductor wafer or other disc wafer are provided. The inspecting device is configured having image capturing means 130a, 130b for capturing an image of an outer edge and its neighboring region of a rotating wafer 10, wafer outer edge position measuring means 200 for measuring the radial direction position of the outer edge at each of the plurality of rotational angle positions θn of the wafer 10 based on the images obtained by the image capturing means 130a, 130b, an edge-to-edge distance measuring means 200 for measuring the edge-to-edge distance Bθn between the outer edge of the wafer 10 and the edge of an insulating film 11 at each of the plurality of rotational angle positions θn based on the images obtained by the image capturing means 130a, and an inspection information generating means 200 for generating predetermined inspection information based on the radial direction position Aθn of the outer edge of the wafer 10 and the edge-to-edge distance Bθn.