The privilege information management system stores a group tree configured with group nodes each representing a group configured with a member enabled to use a privilege, stores an object tree configured with object nodes each representing a target object to be used with a privilege, stores, in a releasable manner, privilege-valid link information indicating a connection between an arbitrary group node and an arbitrary object node in a privilege-valid mode, and regarding a first group node of the group nodes and a first object node of the object nodes connected by the privilege-valid link information, grants a privilege to use a target object of the first object node and a subordinate object node if there are any under the first object node to a member belonging to the first group node and a subordinate group node if there are any under the first group node.