In this study it is intended to develop the ontology which can express the relation between objects with emphasis on the structural representation of semantics. Its interoperability with other kinds of previous ontology and metadata was also considered so that the developed ontology may be applicable to the real situation. The ABC Ontology can get extended into another field where the application of the concept of event is Possible, for ABC Ontology Provides the fundamental framework on the axis of event. In this study it is Music where ABC Ontology can be applied properly, which results in creating Music Ontology. Music Ontology Provides the infrastructure of knowledge for reasoning of Potential meaning as well as the simple semantic connection of terms. The extended model of ABC Ontology has been developed by applying Music Ontology, which is the domain ontology and conveys meaning, to ABC Ontology that represents the whole framework. The representation of conceptual relation in ABC Ontology turns into the association of the framework and meaning in the extended model of ABC Ontology, with reasoning rules which are typical in ontology Also, interoperability of the extended model of ABC Ontology is examined in consideration of co-operating with metadata different from those in it.