Abstract: A document diagnostic program is provided for reducing a check operation checking whether or not a described term is appropriately used with regard to a document whose description content is sectioned by identifiers. The reading means 18 of the computer 11 imports the character data of the specification whose description content is sectioned by a predetermined identifiers from a flexible disk 21 together with the identifiers, and the control means 16 detects a predetermined indication refernee term from the character data of the description content sectioned by the identifiers. Then, the control means 16 searches whether or not the character string which is identical with the character string modified by the indication term exists in the character data of the description content prior to the indication term based on the document diagnostic program.