1. A information extraction rule making support system comprising: a storage section for storing an extraction object document, which is an electronic document of an information extraction object; an input section for inputting a plurality of extraction rules, which are rules used to extract information from said extraction object document; an information extraction section for respectively deriving extraction results matching each of said extraction rules from said extraction object document stored by said storage section, using each of said extraction rules inputted by said input section; and a rule relation creating section for creating a rule relation network indicating a relation between each of said extraction rules by analyzing an overlapping relation or including relation between extraction results derived by said information extraction means and linking each of said extraction rules based on the result of the analysis.