Abstract: How to make use of the existing data resources to construct ontology(semi)automatically is one of the tasks of achieving Semantic Web. By analyzing the current research results and deficiency, a systematic approach to OWL ontology construction based on RDB was presented. Described the processing steps of extracting the semantic information from RDB including entity, relation, inheritance, aggregation and cardinality ratio constraint. Accomplished the transformation from RDB semantic information to corresponding elements of ontology. Prototype system implementation demonstrates the effectiveness of the approach.

Key words: RDB, OWL, Semantic Web, Ontology construction