PROBLEM TO BE SOLVED : To flexibly cope with an inquiry about real estate for public work projects, and to easily and quickly retrieve book information and map information on the real estate.SOLUTION : On the public work projects GIS side of this real estate register information retrieving system for the public work projects, attribute information on the real estate for the public work projects is stored in a real estate register database RR with every record specified by specific attribute information. The respective records are linked with real estate position data of a position database GP via a land property database TB. Material information on the real estate for the public work projects is arranged and filed in a material data file DF of a material file system. A material control database FM for controlling material data is linked with the land property database TB by a document file link database FR, and since GIS and the file system are mutually linked, for example, a user can make access to material information DF in a route of the database RR→TB→FR→FM.