The invention relates to a large file comparison method and comparison system based on data characteristic codes.The method comprises the following steps of a characteristic code extraction and comparison step, wherein data characteristic codes are extracted for a large file, characteristic code files are generated according to the data characteristic codes, and comparison is conducted on the characteristic code files to see whether the characteristic code files are consistent or not; a file splitting step, wherein under the situation that the comparison results of the characteristic code files are consistent, on the basis of the characteristic code files, the large file is split to generate split N subfiles; a subfile comparison step, wherein comparison is conducted on the N subfiles concurrently; a result merging step, wherein comparison results obtained in the subfile comparison step are merged.According to the large file comparison method and comparison system based on the data characteristic codes, the data processing efficiency can be improved, the resource requirement is low, and the system can be run normally even on a machine with low configuration.