This study aims to develop an ontology-based knowledge organization system (KOS) for intangible cultural heritage (ICH). The proposed methodology applies ontology techniques to construct a structured knowledge framework, enhancing knowledge sharing and reuse, which are critical components in knowledge-based management systems. We developed the ICH ontology model using the HOZO ontology editor, enabling us to classify and arrange ICH knowledge hierarchically into five sub-domains: Oral Traditions, Performing Arts, Social Practices, Rituals and Festive Events, Knowledge and Practices Concerning Nature and the (...) Universe, and Skills to Produce Traditional Crafts. To ensure the quality and effectiveness of the ontology, researchers used the WIDOCO tool for comprehensive documentation and employed the Oops! (Ontology Pitfall Scanner) tool to identify and rectify common pitfalls. The ontology was made publicly accessible via a dedicated web portal, facilitating its use by other researchers and contributing to the advancement of ICH informatics. Additionally, a semantic search application demonstrated the practical utility of the ontology, showcasing its capacity to handle complex queries. The evaluation process confirmed the ontology's robustness, ensuring its alignment with contemporary trends in digital humanities and semantic web technologies. This research underscores the significance of a well-structured ontology in enhancing the understanding, preservation, and dissemination of ICH, providing a robust framework for future advancements in the field. (shrink)