Auditing against Generic Management System requirements, like requirements of ISO 9001, is an established means for evaluating organizational capabilities. In ISO 9001, auditors check individual management system based on generic management system standards. Auditors faced with semantic problems because they must interpret the meaning of individual complex management system from the stand point of generic management system standards. To solve this semantic problem, audit support system has been developed using ontology editor. However the audit support system is not widespread, because the ontology editor is so complex. In ontology editor Protégé, too many functions for the ontology operations are provided. The main objective of this paper is to develop a new audit support plug-in system, which supports auditors who don't know about ontology concepts will be able to solve the semantic problems. In this paper, first we analyze complexity of conventional audit support system. Next, we construct plug-in system that is customized in audit by the use of Protégé plug-in function.