PURPOSE: To efficiently execute operation for documentation, to prevent the generation of mistransfer and to prepare a design document with high quality by providing this comment extracting system with a means for respectively extracting and documentating comments relating to respective modules constituting a source program and comments relating to data and procedures in respective modules.

CONSTITUTION: Comments relating to respective modules to be reference elements constituting the source program 110 are extracted, documentated and stored in a module comment table 107, comments relating to data in respective modules are extracted, documentated and stored in a data comment table 108 and comments relating to procedures in respective modules are extracted, documented and stored in a procedure comment table 109. Respective comments are automatically judged and documentated as a part of specifications without depending upon manual operation.