An inspection apparatus obtains a scanned image by reading a printed product, calculates a weighting factor of a weighting filter based on a difference between a value of a pixel of interest in a reference image used in creation of the printed product and values of peripheral pixels of the pixel of interest, performs filter processing by using the weighting filter having the weighting factors, with respect to a pixel of interest in the scanned image, which corresponds to the pixel of interest in the reference image, thereby shifting the pixel of interest in the scanned image, and create an inspection target image by calculating the weighting factors and performing the filter processing with respect to the shifted pixel of interest, and inspects quality of the printed product by collating the inspection target image with the reference image.