Procedure for verifying the integrity of documents which comprises a characterization of the original document to obtain a hash (508) and a stage of integrity verification, this stage comprising in turn, representing (601) the digital document to be verified in a matrix format; adapting (602) said document to a determined resolution in the characterization and correcting (603) the inclination, obtaining a corrected image (604); obtaining (605), the displacement produced between the contents in the original document and the document to be verified; obtaining (610) optimal displacement coordinates for each one of the regions of the corrected image; obtaining (611) one metric from the quantified coefficients of the corrected image and the corresponding ones in the original document; deciding (612) on the integrity of each region of the digitalized document using the previous metrics; and finally deciding (613) on the integrity of the document based on the results of the previous step.