To accurately inspect (recognize) a defect of a product mark and to accurately inspect the external appearance of the product.

In the method for inspecting the detect of contour shape, a template image is inputted, edge information of the inputted template image is extracted, distortion of the extracted edge information is corrected, an R-table is prepared from the corrected edge information, and the R-table is used to prepare a defect check template for a two-dimensional image; besides a work image is inputted, edge information of the work image is extracted, the R-table is used to perform generalization Haugh transform of the edge information subjected to distortion correction, the position, angle and size of the transformed information are corrected, an edge image is reproduced from the corrected edge information, and the reproduced edge image is compared with the defect check template to inspect the defect with the difference image.