A structural object information search unit (18) acquires structural object specification information of the target structural object from the inspection result information, and searches for structural object information of a reference structural object stored in a structural object information DB (50). The structural object information search unit (18) specifies similar reference structural object similar to the target structural object. An inspection result similarity determination unit (24) acquires inspection and/or repair information of the similar reference structural object from the structural object information DB (50), compares the inspection and/or repair information of the similar reference structural object with a inspection result of the target structural object, and specifies inspection result information of the reference structural object used in generation of a repair plan. The repair plan generation unit (20) generates a repair plan of the target structural object based on the specified inspection result information.