XML documents might often conform to different schemas even in the same application domain. To support the interoperability among different IT systems, this paper proposes a sophisticated method for integrating XML schemas. The proposed method determines the synonym, hypernym, and holonym relationships among XML elements and attributes by using domain ontologies as well as general dictionaries. Specifically, the proposed method takes the structural information of elements and attributes into account. The conciseness of the schema integrated is also considered. Experimental results with a variety of schemas show that the utilization of a domain ontology and the structural information improved the performance of schema integration.