An application server management system which makes a plurality of virtual server instance sections representing an identical server operate by setting values different from each other is provided. Included are: a management apparatus having a difference extraction section that extracts a setting item which is different among pieces of virtual server instance section representing an identical server; and an application server having a setting information management section that identifies an object holding a current setting value of the setting item having difference, a duplicate object generation section that makes a duplicate object of a setting value holding object hold the setting value having difference, an object repository that correlates duplicate object reference information, the class of a setting value holding object and application information, and an object invoking intervention section.