1. A printing apparatus for printing an image stored in a mounted storage medium, comprising: determination means for determining whether a second image being a duplicate of a first image stored in the storage medium exists; printing inhibition means for inhibiting printing of the second image determined by said determination means, in a case of printing images stored in the storage medium; image processing means for reading out image data of images to be printed except for the second image inhibited by said printing inhibition means from the storage medium and converting the image data to generate print data; and printing means for printing in accordance with the print data generated by said image processing means.