PROBLEM TO BE SOLVED : To provide a registration information management device and a registration information management system for managing registration information including registration identification information.SOLUTION : This registration information management device is provided with : a database for storing real estate information, acceptance information, person concerned information and registration identification information for specifying a registered security right; an acquisition means for acquiring register information from a register information providing server, based on designated real estate information; a first extraction means for, when there is parent property relating to the sub-division of lot about the object security right, extracting at least real estate information for specifying the master property from the register information acquired by the acquisition means; and a reading means for reading at least the registration identification information from among the corresponding real estate information, acceptance information, person concerned information and registration identification information from the database based on the real estate information, acceptance information and person concerned information.COPYRIGHT : (C)2007, JPO&INPIT