To provide a system which sharply reduces a load to a system when calling document images read by a scanner when retrieving and raises the speed of retrieving, browsing, downloading and editing.

When changing document image data read by the scanner into a tag form image format, the system generates individual image files for each page, saves a text data file obtained by conducting OCR processing to the individual image file by giving an identifier and character coordinate information common to the image file, calls the image file which has the identifier common to the text file having character information in agreement with the retrieval character, and highlights the retrieval object when receiving a retrieval request.